Also found in: Dictionary, Thesaurus, Medical, Legal, Encyclopedia, Wikipedia.

*armed and dangerous

Cliché [of someone who is suspected of a crime] having a gun or other lethal weapon and not being reluctant to use it. (This is part of a warning to police officers who might try to capture an armed suspect. *Typically: be ~; be regarded as ~; be presumed to be ~.) The murderer is at large, presumed to be armed and dangerous. The suspect has killed once and is armed and dangerous.
See also: and, arm, dangerous

little knowledge is a dangerous thing

 and little learning is a dangerous thing
Prov. Cliché If you only know a little about something, you may feel you are qualified to make judgments when, in fact, you are not. After Bill read one book on the history of Venezuela, he felt he was an authority on the subject, but he wound up looking like a fool in discussions with people who knew a lot more about it than he did. A little learning is a dangerous thing.

on shaky ground

 and on dangerous ground
Fig. [of an idea or proposal] on an unstable or questionable foundation; [of an idea or proposal] founded on a risky premise. When you suggest that we are to blame, you are on shaky ground. There is no evidence that we are at fault. The case for relying solely on nuclear energy seems to be on dangerous ground.
See also: ground, shaky

on dangerous ground

likely to cause offense I know I'm on dangerous ground here, but it is a fact that some women do not find motherhood to be a magical experience.
See also: dangerous, ground

on shaky ground

not supported very well Despite high retail prices and growing demand, the beef industry is still on shaky ground.
See also: ground, shaky

live dangerously

to not worry about the risks involved in your actions She always felt a powerful attraction to men who lived dangerously.
Related vocabulary: (live) on the edge
See also: live

on dangerous ground

if you are on dangerous ground, you are talking about a subject which might upset or offend people The author is on dangerous ground when he starts criticizing modern women's literature. She sensed she was treading on dangerous ground when her father began to look rather annoyed.
See also: dangerous, ground

little knowledge is a dangerous thing, a

Also, a little learning is a dangerous thing. Knowing a little about something tempts one to overestimate one's abilities. For example, I know you've assembled furniture, but that doesn't mean you can build an entire wall system; remember, a little knowledge . This maxim, originally a line from Alexander Pope's An Essay on Criticism (1709), has been repeated with slight variations ever since. It is still heard, although less frequently, and sometimes shortened, as in the example.

live dangerously

Take numerous risks, be daring, as in Bill never knows if he'll have enough money to pay the next month's rent-he likes to live dangerously . This expression figured in the work of such 19th-century German writers as Nietzsche, who regarded it as an admirable course of action. Today it is often used with mildly humorous effect, as in the example. [c. 1900]
See also: live
References in classic literature ?
I shall be told, that however dangerous this mixture of powers may be in theory, it is rendered harmless by the dependence of Congress on the State for the means of carrying them into practice; that however large the mass of powers may be, it is in fact a lifeless mass.
The poor partisan, therefore, was fain to leave his vagabonds among these birds of their own feather, and being too weak in numbers to attempt the dangerous pass across the mountains to meet Captain Bonneville on Salmon River, he made, with the few that remained faithful to him, for the neighborhood of Tullock's Fort, on the Yellowstone, under the protection of which he went into winter quarters.
At length the reflux of the tide, and the springing up of the wind, enabled them to quit their dangerous situation and take shelter in a small bay within Cape Disappointment, where they rode in safety during the residue of a stormy night, and enjoyed a brief interval of refreshing sleep.
It was a very short day's run, but the dragoman does not want to go further, and has invented a plausible lie about the country beyond this being infested by ferocious Arabs, who would make sleeping in their midst a dangerous pastime.
The doctor dared hesitate no longer; and, throwing out a fragment of quartz, he kept himself beyond the reach of these dangerous assailants; and, for two hours afterward, he could see them wandering hither and thither through the darkness of the night, until, little by little, their light diminished, and they, one by one, died out.
Guph knew very well that the Phanfasms would be almost as dangerous to the Nomes as they would to the Ozites, but he thought himself so clever that he believed he could manage these strange creatures and make them obey him.
That makes a war with them dangerous, and a dangerous war cannot be a pleasant one.
It was a long shot, a dangerous shot, for unless one is accustomed to it, shooting from a considerable altitude is most deceptive work.
Feeling in a daring mood, she released her pretty hair from the braids in which she usually wore it and permitted the curls to display themselves in all their brown abundance, especially several dangerous little ones about the temples and forehead.
As the tongue was removed for the high priest's table, "Ah," said the Idol to himself, "that is the Sword of the Spirit - the only Sword that is less dangerous when unsheathed.
Whisky was dangerous like other dangerous things in the natural world.
Popular opinion in England seems to me to be, not only getting to consider the cultivation of the muscles as of equal importance with the cultivation of the mind, but to be actually extending--in practice, if not in theory--to the absurd and dangerous length of putting bodily training in the first place of importance, and mental training in the second.
A dangerous crossing, a dangerous wayfaring, a dangerous looking-back, a dangerous trembling and halting.
Vronsky's wound had been a dangerous one, though it did not touch the heart, and for several days he had lain between life and death.
It was impossible for me to tell her the whole truth without, at the same time, entering into particulars on the subject of the conspiracy, which it would have been dangerous to confide to a stranger.