(transitive, idiomatic) To confront; to abash by stern looks.

To fiddle (play aimlessly). / (UK, dated) To dote on.

(informal) Synonym of yuck factor

Having two functional faces. / deceitful; hypocritical; treacherous

(travel industry, aviation) (Formerly, no longer in use) An IATA defined amount used to adjust Fare Construction Units in international airfare calculations.

Having the striking surface convex; said of hammers.

(mathematics, combinatorics) For an odd integer, the result of multiplying all the odd integers from 1 to the given number; or for an even integer, the result of multiplying all the even integers from 2 to the given number; symbolised by a double exclamation mark (!!). For example, 9!! = 1 × 3 × 5 × 7 × 9 = 945.

(molecular biology, genetics) A protein that binds to specific DNA sequences, thereby controlling the flow (or transcription) of genetic information from DNA to mRNA.

(slang) The facial expression made during orgasm.

(idiomatic) actually, in truth