"one who studies the Lepidoptera," 1826, from Lepidoptera + -ist. Related: Lepidopterology.
Entries linking to lepidopterist
Lepidoptera n.
order of insects with four scaly wings, 1773, the biological classification that includes butterflies and moths, coined 1735 in Modern Latin by Swedish botanist Carolus Linnaeus (Karl von Linné, 1707-1778) from lepido- "scale" + pteron "wing, feather" (from PIE root *pet- "to rush, to fly"). Related: Lepidopteral; lepidopteran; lepidopterous.
-ist
word-forming element meaning "one who does or makes," also used to indicate adherence to a certain doctrine or custom, from French -iste and directly from Latin -ista (source also of Spanish, Portuguese, Italian -ista), from Greek agent-noun ending -istes, which is from -is-, ending of the stem of verbs in -izein, + agential suffix -tes.
Variant -ister (as in chorister, barrister) is from Old French -istre, on false analogy of ministre. Variant -ista is from Spanish, popularized in American English 1970s by names of Latin-American revolutionary movements.