"incapable of being satisfied or appeased; inordinately greedy," early 15c., insaciable, from Old French insaciable "ravenous" (15c., Modern French insatiable), or directly from Latin insatiabilis "not to be satisfied," from in- "not, opposite of" (from PIE root *ne- "not") + satiabilis, from satiare "fill full, satisfy," from satis "enough" (from PIE root *sa- "to satisfy"). Related: Insatiably; insatiableness.
It forms all or part of: assets; hadron; sad; sate; satiate; satiety; satisfy; satire; saturate; saturation.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit a-sinvan "insatiable;" Greek hadros "thick, bulky;" Latin satis "enough, sufficient;" Old Church Slavonic sytu, Lithuanian sotus "satiated;" Old Irish saith "satiety," sathach "sated;" Old English sæd "sated, full, having had one's fill, weary of."
As a psychological disorder, technically bulemia nervosa. Englished form boulimy, bulimy was used from late 14c. in a medical sense of "morbidly ravishing hunger, disease causing the patient to have an insatiable hunger for food."