Wiktionary
unibody
n. 1 (context uncountable automobiles English) An automobile construction technique in which the body is integrated into a single unit with the chassis rather than having a separate body-on-frame. 2 (context countable automobiles English) A body of this type. 3 (context countable uncountable English) A shell that is the principal source of structural strength of an object; also, its design and construction.