Any of various aphidlike insects of the family Adelgidae that infest conifers and usually secrete a waxy or woolly covering.
[From New Latin Adelgidae, family name, from Adelgēs, type genus, from -adelges (interpreted as "suckers"), in French Phytadelges, former adelgid family name (PHYT(O)- + -adelges, literally "plant-suckers"), and French Zoadelges, former family of hemipterans including the bedbug (ZO(O)- + -adelges, literally "animal-suckers"), both coined by French zoologist André Marie Constant Duméril (1774-1860), from adelgein, probably misreading of Greek amelgein, to milk, suck up, drain, drink; see melg- in the Appendix of Indo-European roots, or possibly misreading of athelgein, a rare verb said to mean the same thing as amelgein in a 4th-century AD Greek dictionary.]
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