In full gamma-butyrolactone. An oily liquid γ-lactone used as a solvent and sometimes also taken as a recreational drug (being metabolized to GHB in the body).
Systematic name: dihydrofuran-2(3H)-one; C4H6O2..
Origin
Late 19th century; earliest use found in Science. From butyro- + lactone, after German Butyrolakton.