(e.g. of a sportsman or athlete) playing for pay on a part-time basis / (of a team) composed of semi-professional players

a semi-professional sportsman or athlete

Partially automatic. / Of a firearm that automatically ejects a shell and loads the next one, but requires the trigger to be squeezed for each shot; autoloading.

(weaponry) A semi-automatic firearm, especially such a pistol. / (automotive) A semi-automatic transmission.

Alternative spelling of semifinal

(mathematical analysis) A function denoted ∥v∥ that maps a vector v to a non-negative value such that ∥cv∥ = |c|.∥v∥, where c is a scalar, and ∥v + w∥ ≤ ∥v∥ + ∥w∥ (the triangle inequality); the condition that ∥v∥ = 0 implies that v = 0 is not required, but when it holds, the semi-norm is a norm.

of milk, from which about half of the cream has been removed

Of a verb whose present system is normal but its perfect system is deponent.

A verb of this kind.

Of a house: joined to another one on one side, having one shared wall.