'lenslike' is built from 'lens' + the English suffix '-like'. 'Lens' originates from Latin, specifically the word 'lēns', where 'lēns' meant 'lentil' (used because of the similar shape); the suffix '-like' comes from Old English 'līc' (via Middle English '-like'), where 'līc' meant 'having the form of' or 'similar to'.

'lens' passed from Latin 'lēns' into Medieval/Latin use and then into Middle English as 'lens'; the adjectival/forming element '‑like' developed from Old English 'līc' to Middle English '-like' and combined with nouns to form adjectives such as 'lenslike' in modern English.

Initially 'lens' referred to a 'lentil' (from which the shape analogy arose); over time the term came to denote the optical element with that shape, and compounds like 'lenslike' came to mean 'lentil‑shaped' → 'lens‑shaped' and, by extension, 'having lenslike (focusing) properties'.