divideyoudaoicibaDictYouDict[divide 词源字典]
divide: [14] Etymologically, divide shares its underlying notion of ‘separation’ with widow ‘woman parted from or bereft of her husband’, which comes ultimately from the same source. English acquired it from Latin dīvidere ‘split up, divide’. This was a compound verb formed from the prefix dis- ‘apart’ and -videre, a verbal element meaning ‘separate’ which is represented in Sanskrit vindháte ‘is empty’ as well as in widow, and goes back to an Indo-European base *weidh- ‘separate’.

English device and devise come ultimately from *dīvisāre, a Vulgar Latin derivative of dīvidere, and individual belongs to the same word family.
=> device, individual, widow[divide etymology, divide origin, 英语词源]
divide (v.)youdaoicibaDictYouDict
early 14c., from Latin dividere "to force apart, cleave, distribute," from dis- "apart" (see dis-) + -videre "to separate," from PIE root *weidh- "to separate" (see widow; also see with).

Mathematical sense is from early 15c. Divide and rule (c. 1600) translates Latin divide et impera, a maxim of Machiavelli. Related: Divided; dividing.
divide (n.)youdaoicibaDictYouDict
1640s, "act of dividing," from divide (v.). Meaning "watershed, separation between river valleys" is first recorded 1807, American English.