'mushroom-like' is a compound word formed from 'mushroom' and the suffix '-like', which is used to form adjectives meaning 'resembling or characteristic of'.

The word 'mushroom' comes from the Old French 'mousseron', which was derived from the Latin 'mussirio'. The suffix '-like' has been used in English since the Middle Ages to form adjectives.

The term 'mushroom-like' has consistently meant 'resembling a mushroom' since its formation.