[ 'ɔ:tə(ʊ)kleɪv ]
■ noun a strong heated container used for chemical reactions and processes using high pressures and temperatures, e.g. steam sterilization.
■ verb heat in an ~.
Origin
C19: from Fr., from auto- 'self' + L. clavus 'nail' or clavis 'key' (so named because it is self-fastening).