thyridium

noun

thy·​rid·​i·​um

-dēəm

plural thyridia

-ēə

1

: a pale spot in the wing vein of some insects especially of the orders Hymenoptera and Trichoptera

2

: one of a pair of oval pits on the second abdominal tergite of some hymenopterans

Word History

Etymology

New Latin, from Greek thyridion window, diminutive of thyra door

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