A simplified drawing of a smiling face, using two dots for the eyes and an arc for the mouth. / (rare) A smiley.

(military) An abrupt turn to face the opposite direction. / A reversal in direction; a reversal of attitude or opinion.

(intransitive) To turn 180 degrees to face the opposite direction. / To change opinion or attitude drastically.

(mathematics) A prime number that is one more or one less than a factorial. For example, 7 is a factorial prime, since 3! + 1 = 7.

(mathematics, combinatorics) The result of multiplying a given number of consecutive integers from 1 to the given number. In equations, it is symbolized by an exclamation mark (!). For example, 5! = 1 × 2 × 3 × 4 × 5 = 120.

(mathematics) Of or pertaining to a factor or factorial. / Of or pertaining to a factor, a kind of business agent. / (dated) Of or pertaining to a factory.

(idiomatic, cricket) To turn the face of the bat inwards, in order to hit the ball to the leg side.

(soccer) Initialism of Football Association, especially the English Football Association. See also Scottish FA and Welsh FA.

(vulgar) Initialism of fuck all. / (euphemistic) Initialism of Fanny Adams.

Initialism of Fanconi anemia. / (Wikipedia) Initialism of featured article. / Initialism of felonious assault. / Initialism of flight attendant. / Initialism of fee agreement.