First attested in the Bullyu dugong busi eonhae (分類杜工部詩諺解 / 분류두공부시언해), 1481, as 옫바미(Yale: wotpami). Other obsolete forms: 올바미 (olbami). Likely a compound of 울— (ul-, “to cry, to growl”) and 밤 (bam, “night”), with the nominalisation agent suffix —이 (-i), i.e. "the thing that cries at night" (cf. 올빼미의 어원).