(baseball) Catcher's equipment

(medicine, archaic) A variety of bandy leg, associated with partial dislocation of the tibia, once seen in young children who worked in factories.

(aviation, transitive, intransitive) To align (an aircraft) with the runway, usually by means of rudder or rudderon input, immediately before, simultaneously with, or immediately after touchdown du...

(geometry) The single (up to logical equivalence) geometry whose axiomatic system is equivalent to that of Euclidean geometry without the parallel postulate or any alternative.