'metafictional' originates from English formation: the noun 'metafiction' + the adjectival suffix '-al'. 'metafiction' itself is built from the prefix 'meta-' and the noun 'fiction'.

'metafictional' formed in the mid- to late-20th century from 'metafiction' (a term popularized in literary theory in the 1960s–1970s) and the suffix '-al'. 'metafiction' was coined in English by combining Greek 'meta-' (about/beyond) with 'fiction' (from Latin 'fictio').

Initially, the components meant 'meta-' = 'after/beyond/about' and 'fiction' = 'a shaping or making' (from Latin 'fingere'); over time the compounded term 'metafictional' came to mean specifically 'pertaining to fiction that self-consciously comments on its own fictional nature.'