(baseball, transitive) After a fly ball is caught, to tag the base (a runner) was on at the time of the pitch, thereby causing them to be out for failure to tag up.

(set theory) The axiom that the power set of any set exists and is a valid set, which appears in the standard axiomatisation of set theory, ZFC.

To gain the advantage in a contest.

(poetic) gold

plural of mother-of-pearl

(set theory) A weaker form of the axiom of choice that states that every countable collection of nonempty sets must have a choice function; equivalently, the statement that the direct product of a countable collection of nonempty sets is nonempty.

A female prostitute or courtesan.

plural of lady of pleasure

(palmistry) The elevation at the base of the thumb.

plural of mount of Venus