cheapdate

Coined by Monica S. Moore et al. in 1998 (see 1998 quotation), from “cheap date”, the idea being that it is less expensive to buy an evening's worth of drinks for a person with a lower tolerance for alcohol. (Fruit-fly mutants are frequently given whimsical names.)

cheapdate

1. (always italicized) A certain mutant strain of fruit fly (Drosophila melanogaster) with heightened sensitivity to ethyl alcohol (ethanol), causing it to lose postural control at lower concentrations of the drug.
   • 1998 June 12, Monica S. Moore et al., “Ethanol Intoxication in Drosophila: Genetic and Pharmacological Evidence for Regulation by the cAMP Signaling Pathway”, in Cell, volume 93, number 6, page 998:

     One X-linked mutation isolated in this screen was named cheapdate (chpd) to reflect the increased ethanol sensitivity displayed by hemizygous mutant male flies.

• Robert Krulwich, “Fruit Fly Scientists Swatted Down Over 'Cheap Date'”, npr.org (9 February 2009).

• heptadeca-