'nonwarlike' originates from Modern English, specifically formed from the negative prefix 'non-' and the adjective 'warlike', where 'non-' meant 'not' and 'warlike' meant 'like war' (from 'war' + the suffix '-like').

'non-' was borrowed into Middle English (from Latin 'non' via Old French) as a productive negative prefix; 'war' comes from Old North French 'werre' (Modern French 'guerre') and ultimately Germanic sources, and the suffix '-like' comes from Old English '-līc'. These elements combined in Modern English to produce 'warlike' and then 'nonwarlike'.

Initially the parts meant simply 'not' + 'like war', and over time the combined adjective has retained that literal sense, used to describe attitudes, policies, or states that are not warlike or not inclined to use military force.