'carnation-like' is formed from the noun 'carnation' + the adjectival suffix '-like'. 'Carnation' originates from Latin 'carnatio' (from 'caro, carnis' meaning 'flesh'), and the suffix '-like' comes from Old English '-lic' meaning 'having the form of' or 'similar to'.

'carnation' entered English via Old French/Medieval Latin from Latin 'carnatio' meaning 'flesh-colour' (referring to the flower's flesh-like or pink color). The productive English suffix '-like' (from Old English '-lic') was later attached to form comparative adjectives such as 'carnation-like'.

Initially 'carnation' referred to a flesh-colour (from Latin 'flesh'), then to the flower named for that color; 'carnation-like' therefore evolved to mean 'resembling the flower' or 'having the flower's characteristic color', which is the modern usage.