wardyoudaoicibaDictYouDict[ward 词源字典]
ward: [OE] Ward and guard are ultimately the same word. Both go back to a prehistoric West Germanic *wartho ‘watching over’. But whereas guard reached English via Old French, ward is a lineal descendant of the Germanic word. The noun originally meant ‘watching, guarding’; its application to an individual room of an institution where people are guarded or looked after (at first including prisons as well as hospitals) dates from the 16th century.

The verb ward (now mainly encountered in ward off) comes from the Germanic derivative *warthōjan. The early sense ‘guardianship, custody’ is preserved in such expressions as ward of court, and also in warden [13] (from the Old Northern French derivative wardein, corresponding to the central French form guardien ‘guardian’) and warder [14], from Anglo-Norman wardere.

The word’s ultimate source is the base *war- ‘watch, be on one’s guard, take care’ (source also of English aware, beware, warn, wary, etc).
=> aware, beware, guard, warn, wary[ward etymology, ward origin, 英语词源]
ward (n.)youdaoicibaDictYouDict
Old English weard "a guarding, protection; watchman, sentry, keeper," from Proto-Germanic *wardaz "guard" (cognates: Old Saxon ward, Old Norse vörðr, Old High German wart), from PIE *war-o-, from root *wer- (4) "perceive, watch out for" (cognates: Latin vereri "to observe with awe, revere, respect, fear;" Greek ouros "a guard, watchman," and possibly horan "to see;" Hittite werite- "to see"). Used for administrative districts (at first in the sense of guardianship) from late 14c.; of hospital divisions from 1749. Meaning "minor under control of a guardian" is from early 15c. Ward-heeler is 1890, from heeler "loafer, one on the lookout for shady work" (1870s).
ward (v.)youdaoicibaDictYouDict
Old English weardian "to keep guard, watch, protect, preserve," from Proto-Germanic *wardon "to guard" (cognates: Old Saxon wardon, Old Norse varða "to guard," Old Frisian wardia, Middle Dutch waerden "to take care of," Old High German warten "to guard, look out for, expect," German warten "to wait, wait on, nurse, tend"), from PIE *war-o- (see ward (n.)). French garder, Italian guardare, Spanish guardar are Germanic loan-words. Meaning "to parry, to fend off" (now usually with off) is recorded from 1570s. Related: Warded; warding.