0-day

Used to describe a software security vulnerability that has just been exploited or discovered, often before the software developers can formally announce or create a fix (thus giving them "zero days" to preemptively address the issue). It was a 0-day attack—the developers had no idea that their program could be hacked in that way. Please tell me that our software is well-protected against zero-day exploits. Because it was a 0-day attack, it's going to take time for us to get the site back up and running again.

go from zero to hero

To change an outcome, one's situation, or oneself from being particularly unsuccessful, negative, unfortunate, or unpopular to being especially successful, positive, fortunate, or popular. After his parents won the lottery, John went from zero to hero in his high school overnight. With computer programming becoming an increasingly in-demand skill, many who might have been picked on in high school are now going from zeros to heroes. The principal went from zero to hero when he let us go home early after the power outage.

go from zero to sixty

1. To accelerate from a standstill to sixty miles per hour. Used to indicate how quickly a vehicle, especially an automobile, can accelerate. It may not look impressive on the outside, but this bad boy can go from zero to sixty in about five seconds flat. That old junker can go from zero to sixty? Yeah, right—I bet it can't get up to 60 mph at all! I don't care if your car can go from zero to sixty, and I really don't want to be in the car when it does!

2. To abruptly and dramatically increase or intensify something. No, this isn't a demotion—I just don't want you to go from zero to sixty right after a major surgery. Play a few games in the minors first and see how you feel. A: "Aaah! Is that your alarm or a fire bell?" B: "Yeah, it really goes from zero to sixty on the volume, huh? Sorry about that." I have no desire to go from zero to sixty, so I'm starting out with five pound weights.

3. To change from a calm or neutral demeanor to an extreme, excessive reaction very quickly. His anger issues are really out of control. He goes from zero to sixty at the slightest provocation! Now that some time has passed since the funeral, I'm doing a little better, but I still go from zero to sixty in a moment if something reminds me of her. Yeah, Mom's going to be upset that you're home past curfew, but she'll go from zero to sixty when she sees that you're also drunk!

ground zero

1. The center or primary location of some disaster. Volunteers at ground zero have been describing scenes of chaos caused by the hurricane's destructive force. We'll set up a post at ground zero and try to reunite family members displaced by the earthquake. Yes, we've heard about the devastating tornado—members of the Red Cross are on their way to ground zero now.

2. The target or location of some violent act of destruction, especially a bombing. The prime minister toured the destruction at ground zero following the enemy bombardment. The president has got to get to ground zero ASAP and show his support for the community affected by the bombing. I never expected my government office building to become ground zero for a terrorist attack—which was probably naïve of me, looking back.

3. The site of New York City's World Trade Center following its destruction during the attacks on September 11, 2001. In this usage, the phrase is usually capitalized. Visiting Ground Zero still leaves me filled with grief beyond words, even after all these years. We visited the World Trade Center on a school trip to New York mere months before 9/11. It's wild to see it again now, as Ground Zero. As soon as Ground Zero came into view, I was instantly reminded of what I was doing on that fateful morning in 2001.

4. The earliest possible starting point; the most basic, fundamental, or preliminary level. The folder with my outline and notes got deleted, so now I have to start the whole project again from ground zero. We don't have time to start from ground zero, so let's just reuse the assets we made for the last project. A: "The teacher didn't approve your topic?" B: "Nope. So now I have to start at ground zero and pick something else."

patient zero

1. The first person to exhibit symptoms of an illness. The phrase originated during the AIDS crisis of the 1980s. My daughter was patient zero, the only one with a cold last week—now, she's very generously given it to the rest of the family.

2. By extension, the first case of or person demonstrating a particular issue or problem. This guy is patient zero for the crashing issue in the app, so let me see what he said in his original email.

start from ground zero

To begin (something) from the earliest possible starting point; to start (something) at the most basic, fundamental, or preliminary level. A noun or pronoun can be used between "start" and "from." The folder with my outline and notes got deleted, so now I have to start the whole project again from ground zero. We don't have time to start from ground zero, so let's just reuse the assets we made for the last project.

zero dark thirty

A non-specific time in the early morning before the sun has risen. Based on the way in which military time is said aloud. Why on earth are we meeting at zero dark thirty? The only thing we should be doing at this hour is sleeping! We'll have to leave at zero dark thirty if we want to reach Las Cruces before sundown.

zero hour

The time at which something starts. I have so much studying left to do before the exam, and zero hour is 8 AM! Zero hour for our vacation is 4:30—the minute we're all done work!

zero in

1. To aim or direct one's line of vision at something. Can you have the camera zero in on that tree? The soldiers zeroed in on the enemy bunker.

2. To get incrementally closer to something, such as a physical location or the understanding of a concept. Authorities were able to zero in on the compound by using satellite imagery. It has taken multiple drafts, but I think I'm finally zeroing in on the right tone for my novel. The fugitive later admitted that he could sense the police zeroing in.

3. To focus one's attention on something. Critics seem to have really zeroed in on a single scene in the film, and I think they're missing some important points elsewhere. I love how my toddler zeroes in on new words when she hears them.

zero in on (something)

1. To aim or direct one's line of vision at something. Can you have the camera zero in on that tree? The soldiers zeroed in on the enemy bunker.

zero out

1. To reset some device that counts or measures something back to zero. A noun or pronoun can be used between "zero" and "out." Make sure you zero out the scales before you weigh the next ingredient. I forgot to zero out the odometer between trips, so I have no idea how far I actually drove that time.

2. To reduce or eliminate something down to zero. A noun or pronoun can be used between "zero" and "out." Buying my fiancée's engagement ring zeroed out my savings account, but it was worth it seeing her face when I proposed. They haven't laid us off yet, but the fact that they zeroed our budget out means it could happen any day now.

zero tolerance

A policy or attitude of accepting absolutely none of some kind of behavior or activity. A reference to laws or legal policies that impose severe penalties for even the most minor infractions. Can be hyphenated if used before a noun as a modifier. Our dad has always had zero tolerance for us skipping our chores or homework. The boss is implementing a zero-tolerance policy for anyone caught taking office supplies home with them.

zero-sum game

A situation, process, competition, or outcome in which the winner's gain is exactly equal to the loser's loss. Poker is a zero-sum game because the amount of money won by one player is equivalent to the amount lost by the other players.

zero in (on someone or something)

to aim directly at someone or something. The television camera zeroed in on the little boy scratching his head. The commercial zeroed in on the glass of cola. Mary is very good about zeroing in on the most important and helpful ideas.

zero tolerance

absolutely no toleration of even the smallest infraction of a rule. Because of the zero tolerance rule, the kindergartner was expelled from school because his mother accidentally left a table knife in his lunch box.

zero in on

1. Aim precisely at a target, as in They zeroed in on the last snipers. [c. 1940]

2. Direct one's attention to, concentrate or focus on, as in We must zero in on the exact combination of ingredients, or The whole class zeroed in on the new assignment. This usage transfers aiming a firearm to directing one's attention. [Mid-1900s]

3. Converge on, close in on, as in The children zeroed in on the electric train display. [Mid-1900s]

a zero-sum game

JOURNALISM

If a situation is a zero-sum game, the advantage that one person gains from it must have an equal disadvantage for someone else. The idea that foreign investment is a zero-sum game — that one country's gain is another's loss — is mistaken. Note: Other nouns are sometimes used instead of game. According to Reed, employee benefits are a zero-sum gain. If costs for one benefit rise, it's often at the expense of another, such as paid vacation and health insurance. Note: A zero-sum game is one in which the winnings and losses of all the players add up to zero.

zero in

1. To aim or focus something, such as a weapon or telescope, toward a specific target or location: The enemy spotted the approaching aircraft and zeroed in their missiles. Zero the telescopes in on the watchtower.

2. To identify with increasing accuracy a property of something, especially its location: We are finally zeroing in on the location of the smuggling ring.

3. To adjust the aim or sight of a weapon by repeated firings: The soldiers fired a few rounds in order to zero in their rifles. I zeroed the gun in at 100 yards.

4. zero in on To direct one's gaze or attention to something: The children zeroed in on the display of toys in the store window.

zero out

1. To reset something, such as a counter or clock, to zero: The timekeeper forgot to zero out the stopwatch in between sprints. I zeroed the odometer out and measured the length of the road.

2. To reduce some quantity to zero: This final payment will zero out your balance on the loan. I called the bank and zeroed out my account.

3. To cut off the funding for something, such as a government program: The new administration is planning to zero out subsidies and benefits for illegal aliens. Our social assistance program had funding until the government zeroed it out of the budget.

zero

n. an insignificant person; a nobody. I want to be more in life than just another zero.

ground zero

The site of any disaster; specifically, and often capitalized (Ground Zero), the site of New York’s World Trade Center, wrecked by airplanes on September 11, 2001. Originally the term designated the central point of a nuclear detonation or similar large blast, but since the attacks of 2001, often referred to simply as nine-eleven, it has been used both specifically and metaphorically. It was first used with reference to the atomic bombing of Hiroshima and Nagasaki in 1945 and then was extended to other disasters, such as earthquakes. Referring to the economic downturn, a character in Ian Rankin’s novel The Complaints (2009) asked, “Does nobody realize this is Credit Crunch Ground Zero?”