extinctyoudaoicibaDictYouDict[extinct 词源字典]
extinct: [15] Latin stinguere appears originally to have meant ‘prick, stick’ (a sense revealed in the derivative from which English gets distinct), but in historical times the only record of it we have is in the later, and rather remote metaphorical meaning ‘quench’. With the addition of the prefix ex- ‘out’ it became extinguere ‘put out’, whence English extinguish [16]. Extinct comes from its past participle, extinctus, and originally meant ‘put out, no longer alight’: ‘That fire was extinct’, Ranulph Higden, Polychronicon 1432– 50.

Its modern use, ‘having died out’, dates – in relation to species, families, etc – from the late 17th century.
=> distinct, extinguish[extinct etymology, extinct origin, 英语词源]
extinct (adj.)youdaoicibaDictYouDict
early 15c., "extinguished, quenched," from Latin extinctus/exstinctus, past participle of extinguere/exstinguere "to put out, quench; go out, die out; kill, destroy" (see extinguish). Originally of fires; in reference to the condition of a family or a hereditary title that has "died out," from 1580s; of species by 1768. Shakespeare uses it as a verb. Compare extinction.