Idioms N
Nail in the coffin A nail in someone's or something's coffin is a problem or event that is a clear step towards an inevitable failure
Nail biter If a game, election, contest, etc, is a nail-biter, it is exciting because the competitors are so close that it is impossible to predict the result
Nature of the beast The basic characteristics of something is the nature of the beast
Neck and neck If two competitors or candidates, etc, are neck and neck, then they are very close and neither is clearly winning
Neck of the woods If someone talks about their neck of the woods, they mean the area where they live
Needle in a hay stack If trying to find something is like looking for a needle in a haystack, it means that it is very difficult, if not impossible to find among everything around it
Neither here nor there If something is neither here nor there, it is of very little importance
Neither use nor ornament Something that serves no purpose and is not aesthetically pleasing is neither use nor ornament
Nest egg If you have some money saved for the future, it is a nest egg
New blood If something needs new blood, it has become stale and needs new ideas or people to invigorate it
New brush sweeps clean A new brush sweeps clean means that someone with a new perspective can make great changes
New kid on the block A new kid on the block is a person who has recently joined a company, organisation, team, etc,
New lease of life If someone finds new enthusiasm and energy for something, they have a new lease of life
Nick of time If you do something in the nick of time, you do it at the very last minute or second
Night owl A night owl is someone who goes to bed very late
Nip and tuck A close contest where neither opponent seems to be gaining the advantage
Nip at the bit If someone is nipping at the bit, they are anxious to get something done and don't want to wait, another one is champ at the bit
Nip it in the bud If you nip something in the bud, you deal with a problem when it is still small, before it can grow into something serious
Nitty gritty If people get down to the nitty gritty, they concentrate on the most important and serious issues
No bed of roses If something isn't a bed of roses, it is difficult
No go Something that will not work, A square peg in a round hole is a no go
No great shakes
If someone is no great shakes at something, they are not very good at it
No holds barred If there are no holds barred, there are no rules of conduct; you can do anything
No ifs or buts Ifs and Buts is a term used to describe the reasons people give for not wanting to do something
No laughing matter Something that is no laughing matter is very serious
No love lost If there is no love lost between two people they have a strong enmity towards or hate for the other and make no effort to conceal it
No pain no gain Means that sometimes something is only achieved with a great deal of effort
No quarter This means without mercy. We can say no quarter given or asked
No questions asked If something is to be done and no questions asked, then it doesn't matter what methods are used or what rules are broken to ensure that it gets done
No skin off my nose If something's no skin off your nose, it doesn't affect or bother you at all
No spring chicken If someone is no spring chicken, they are not young
No strings attached If something has no strings attached, there are no obligations or requirements involved
No time like the present If people say that there's no time like the present , they believe that it is far better to do something now than to leave it for later, in which case it might never get done
No two ways about it If there are no two ways about something, there is no other possible interpretation
No use to man nor beast If something or someone is no use to man or beast, it or they are utterly useless
Nods as good as a wink to a blind horse This is a way of saying you have understood something that someone is said, even though it was not said directly. 
None are so blind as those who don't want to see This idiom is used when people refuse to accept facts presented to them
Nosy parker A nosy parker is someone who is excessively interested in other people's lives
Not a snowballs chance in hell There is absolutely no possibility of something happening if there's not a snowball's chance in hell
Not bat an eyelid If someone doesn't bat an eye, they do not react when other people normally would
Not born yesterday When someone says that they weren't born yesterday, they mean that they are not naive or easily fooled
Not cricket If something is not cricket, it is unfair
Not enough room to swing a cat If a room is very small, you can say that there isn't enough room to swing a cat in it
Not have two pennies to rub together If someone has not got two pennies to rub together, they are very poor indeed
Not my cup of tea If something is not your cup of tea, you don't like it very much
Not on my watch Someone distancing themselves from a situation could say that it is not on their watch
Not our bag If something is not your bag, it is not really suitable for your needs or you don't like it much
Not the only pebble on the beach If something is not the only pebble on the beach, there are other possibilities or alternatives
Notch on your belt A success or achievement that might help you in the future is a notch on your belt
Nothing to crow about If something's nothing to crow about, it's not particularly good or special
Nothing to write home about Something that is not special or good is nothing to write home about
Nothing ventured nothing gained You can't win if you don't join in the game; if you don't participate in something, you will not achieve anything
Null and void If something's null and void, it is invalid or is no longer applicable
Number cruncher A number cruncher is someone who is very good at dealing with numbers and calculations
Nuts and bolts The nuts and bolts are the most essential components of something
Nutty as a fruit cake Someone who's nutty as a fruitcake is irrational or crazy