'anti-deflationary' originates from Modern English, specifically formed from the prefix 'anti-' (from Greek 'anti' meaning 'against') and the adjective 'deflationary' (from 'deflation' + the suffix '-ary'), where 'deflation' was influenced by French 'déflation' and ultimately from Latin components 'de-' (down) and the root 'flare' (to blow).

'anti-deflationary' was coined in modern economic discourse in the late 20th century as a compound of 'anti-' + 'deflationary' and came into use to describe policies or tendencies opposing deflation.

Initially it literally meant 'against deflation'; over time it has come to denote specific policies, measures, or tendencies intended to prevent or counteract falling prices and low demand.