aphid

1. Proto-Indo-European*bʰeyd-“to split”
2. Ancient Greekἀφειδής“unsparing, lavishly borrowed”
3. Ancient Greekκορις“bug”
4. New Latinaphis
5. Englishaphid

From New Latin aphis (plural aphides), coined by Swedish botanist Carolus Linnaeus in 1758. His inspiration for the name remains unclear; OED suggests it might stem from a misreading of Ancient Greek κορις (koris, “bug”) (see diagram), in which case the nominative -ις (-is) suffix was reanalyzed as -ις, -ιδος (-is, -idos); while AHD suggests a connection to Ancient Greek ἀφειδής (apheidḗs, “unsparing, lavishly borrowed”) in reference to the insects' voracity or rapid rate of production, from ἀ- (a-, “not”) + φείδομαι (pheídomai, “to spare, be thrifty, be merciful”), ultimately from Proto-Indo-European *bʰeyd- (“to split”). Doublet of aphis.

More words from New Latin, Ancient Greek, Proto-Indo-European