(mathematics, logic) A unary operation on logical values that changes true to false, and false to true.

(idiomatic, dated) Something of the kind, whatever (used to terminate a vague list).

(as imperative) Do not imitate my behavior but obey my instructions.

absolutely nothing, none of something.

One instance of an event (such as the arrival of a single bird) does not necessarily indicate a trend.

(idiomatic, of the technique for committing suicide) Along the radial artery rather than across the wrist from side to side.

A signal phrase that one does not wish to offend when discussing a potentially contentious issue involving personal beliefs.

(chiefly US, idiomatic) Having no or almost no value; worthless.

(Britain, slang) Not very good; unimpressive.

To be extremely surprised by an event.