be on (one's) mettle

To be determined to succeed and thus prove one's worth, often in a difficult or unpleasant situation. I know my employees think I'm too young to be their supervisor, so I have to be on my mettle every day at the office. I'm not surprised Emily's going to be valedictorian—she's been on her mettle since the first day of freshman year. Because the director was pretty reluctant to give me the part, I will be on my mettle at every rehearsal.

be the exception that proves the rule

To contradict a rule and thus confirm that the rule exists. A: "We're always told to get eight hours of sleep, but I usually feel really groggy when I sleep that much." B: "Well, I guess you're the exception that proves the rule." A: "Video games are all just mindless filth that rots kids' brains." B: "I don't know, a lot of them let kids express themselves creatively or learn about the world in new ways." A: "Bah, those are just the exceptions that prove the rule." A: "But I hardly ever study for tests, and I get good grades." B: "Well, you're the exception that proves the rule—it'll catch up to you eventually!"

See also: exception, prove, rule, that

fend and prove

dated To argue and defend a point or opinion. I was forced to fend and prove my stance before the tribunal. Why must I fend and prove my choices to you, Mother? I am a legal adult, an independent woman. This isn't a courtroom, so I will not fend and prove my beliefs to the likes of you!

have something to prove

To have the need to display and confirm one's abilities to others who are doubtful. His parents expect his art career to fail, so he definitely has something to prove with this upcoming gallery show. Everyone who comes out to Hollywood has something to prove. Do you know how few aspiring actors actually make it? The swimmer did not perform well at the last Olympics, so he has something to prove this time around!

prove (one's) chops

informal To demonstrate or establish that one is skilled in some area. I've heard that you're an excellent piano player. Well, here's a piano—time to prove your chops. Oh no, Tom definitely proved his chops—he stumped me with quite a few of his sports trivia questions. He knows way more than I do.

prove (one's) mettle

To prove that one has endurance and strength of character, or the necessary skills, abilities, or traits to succeed in something. You may be the youngest lawyer in the firm, but you certainly proved your mettle in that high-profile murder case. The new CEO proved her mettle by completely restructuring the dying mobile phone division into the powerhouse it is today.

prove (oneself) as (something)

To do what is necessary to convince others of one's skill, capability, or authenticity in some role. Young men of the tribe are required to prove themselves as hunters before they can assume positions of leadership in the community. They've given me a few freelance projects to prove myself as a copy editor before they agree to hire me on a permanent basis.

prove (something) beyond a reasonable doubt

To demonstrate or establish that something is definitively and incontestably true. Most commonly used in relation to legal proceedings. The jury will acquit him if we don't prove that he's guilty beyond a reasonable doubt.

See also: beyond, doubt, prove, reasonable

prove (something) to (one)

To show or provide evidence that substantiates or makes one believe a claim. This case is your chance to prove your worth to the firm. I want to prove my theory to the panel.

prove (to be) (something)

1. To show or provide evidence of having a particular trait, attribute, or characteristic. The new method proved to be useful in detecting radiation. She's proven a reliable ally in my time at this company.

2. To show or provide evidence that someone, something, or oneself has a particular trait, attribute, or characteristic. In this usage, a noun or pronoun is used directly after "prove." The new computer's incredibly reliable CPU and sleek design prove it to be a worthy investment for any student or professional. The week I had to spend in New York proved Janet to be more than capable of running the office on her own. This new evidence proves him a liar.

prove out

1. To show the validity of something. A noun or pronoun can be used between "prove" and "out." If you can prove out these allegations, that company will soon be faced with a scandal.

2. To succeed. A noun or pronoun can be used between "prove" and "out." My hypothesis still has not proved out, and I can't determine why.

prove to (one) that (something is the case)

To show or provide evidence to one that something is the case. You need to prove to me that you are capable of running this office on your own. This is our chance to prove to the world that our country deserves its place in the global economy.

proving ground

1. A setting in which an idea or product is tested. You better put this product of yours through the proving ground before you make such bold claims about it publicly.

2. A place at which military equipment is tested. Primarily heard in US. A: "What's that loud sound?" B: "They must be working with some equipment over at the Chester Proving Ground."

the exception proves the rule

That which contradicts or goes against a supposed rule therefore proves that it is almost always true. A: "Video games are all just mindless filth that rots kids' brains." B: "I don't know, a lot of them let kids express themselves creatively or learn about the world in new ways." A: "Bah, the exceptions just prove the rule."

the exception that proves the rule

That which contradicts or goes against a supposed rule, and therefore proves it in one's mind. A: "Video games are all just mindless filth that rots kids' brains." B: "I don't know, a lot of them let kids express themselves creatively or learn about the world in new ways." A: "Bah, those are just the exceptions that prove the rule."

See also: exception, prove, rule, that

What does that prove?

1. What crime or wrongdoing does that establish or demonstrate? A: "You're the only one who would have had access to the cash register between those hours." B: "So? What does that prove?" A: "That you're the only person who could have taken the money!"

2. What quality or characteristic does that meaningfully validate or demonstrate? A: "I'm going over there to knock his block off!" B: "And what does that prove? That you're tougher than he is? That you're a real man? All it proves to me is that you're just another hotheaded fool."

What will that prove?

What truth or quality is that going to meaningfully validate or demonstrate? A: "I'm going over there to knock his block off!" B: "And what will that prove? That you're tougher than he is? That you're a real man? All it proves to me is that you're just another hotheaded fool." I thought about lawyering up and taking him to court, but what will that prove? Nothing that will be worth all that time, money, and hassle, that's for sure.

The exception proves the rule.

Prov. Something that does not follow a rule shows that the rule exists. (Often used facetiously, to justify some rule you have proposed but which someone else has listed exceptions. From a Latin phrase meaning that an exception tests a rule.) Ellen: Men are always rude. Jane: But Alan's always polite. And Larry and Ted are polite, too. Ellen: They're just the exceptions that prove the rule. Bill: All the shows on TV are aimed at people with low intelligence. Alan: What about that news program you like to watch? Bill: The exception proves the rule.

prove oneself as something

to demonstrate that one can serve in a certain office or capacity. It's time to promote her. She has proved herself as a teller. I proved myself as an investor by making a lot of money in the stock market.

prove something to someone

to substantiate a claim about something to someone; to make someone believe or accept a statement about something. What do I have to do to prove my innocence to you? Nothing you say will prove it to me.

prove to be something

to be shown to be someone or something; to be found to be someone or something. Susan proved to be a good friend when she lent me some money. The food proved to be spoiled when I smelled it.

What does that prove?

Fig. So what?; that does not mean anything. (A defensive expression. The heaviest stress is on that. Often with so, as in the examples.) Tom: It seems that you were in the apartment the same night that it was robbed. Bob: So, what does that prove? Tom: Nothing, really. It's just something we need to keep in mind. Rachel: You're late again on your car payment. Jane: What does that prove? Rachel: Simply that you can't afford the car and we are going to repossess it.

exception proves the rule, the

An instance that does not obey a rule shows that the rule exists. For example, John's much shorter than average but excels at basketball-the exception proves the rule . This seemingly paradoxical phrase is the converse of the older idea that every rule has an exception. [Mid-1600s]

prove out

Succeed, turn out well, as in Farm-raised trout has proved out so well that the fish industry plans to experiment with other species . [Mid-1900s]

the exception that proves the rule

You say that something is the exception that proves the rule to mean that the example that you have just mentioned is not normal and is the opposite of what you usually find. Towers should generally be arranged in clusters, but the Post Office Tower was the exception that proved the rule — it needs to stand alone so that its signals are not interrupted. The most creative minds are often said to be the product of a problematic childhood, but Hornby must be the exception that proves the rule. Note: `Prove' here means `to test by experiment or analysis' rather than `to establish as true'. So, the meaning is that an exception tests a rule, not that it establishes the rule as true in all other situations.

See also: exception, prove, rule, that

the exception that proves the rule

a particular case that is so unusual that it is evidence of the validity of the rule that generally applies.

This phrase comes from the Latin legal maxim exceptio probat regulum in casibus non exceptis ‘exception proves the rule in the cases not excepted’. This in fact meant that the recognition of something as an exception proved the existence of a rule, but the idiom is popularly used or understood to mean ‘a person or thing that does not conform to the general rule affecting others of that class’

1998 Spectator The success of The Full Monty in the United States is an exception which proves the rule. On such lucky breaks, industries and economies are not built.

See also: exception, prove, rule, that

the exˈception that proves the ˈrule

(saying) people say that something is the exception that proves the rule when they are stating something that seems to be different from the normal situation, but they mean that the normal situation remains true in general: English people are supposed to be very reserved, but Pete is the exception that proves the rule — he’ll chat to anyone!

See also: exception, prove, rule, that

be on, show, prove, etc. your ˈmettle

be prepared to do the best work you can or perform as well as you can in a particular situation: When the boss comes round, I want you all to show your mettle. ♢ He’ll have to be on his mettle if he wants to win the next race.

Mettle is the ability and determination to do something successfully in spite of difficult conditions.

exception proves the rule, the

Although something may not conform to it, the general rule is still valid. This term originated in the 1500s and is considered a proverb. Playwright Thomas Heywood used it in The Rape of Lucrece (1608), “If the general rule have no exceptions, thou wilt have an empty consistory.” However, in the 1800s several scholars maintained that “proves” in this phrase actually means “tests” (and not “verifies”). Whichever is intended, the phrase is still used, as in “Jane was the only woman who opposed this measure; well, the exception proves the rule.”