slip

give someone the slip evade or escape from someone. informal

let something slip

1 reveal something inadvertently in the course of a conversation.

2 fail to take advantage of an opportunity.

let something slip through your fingers (or grasp)

1 lose hold or possession of something.

2 miss the opportunity of gaining something.

❷1925W. Somerset MaughamOf Human Bondage He was mad to have let such an adventure slip through his fingers.

a slip of a - a young, small, and slim person.

1980Philip LarkinLetter After all you are a very young 51! Hardly 51 at all! A slip of a thing!

slip of the pen (or the tongue) a minor mistake in writing (or speech).

☞ The equivalent Latin phrases, lapsus calami and lapsus linguae, are also sometimes used in formal English.

slip on a banana skin make a silly and embarrassing mistake.

slip through the net: seenet.

there's many a slip ('twixt cup and lip) many things can go wrong between the start of something and its completion; nothing is certain until it has happened. proverb