stalkyoudaoicibaDictYouDict[stalk 词源字典]
stalk: English has two distinct words stalk. The noun, ‘plant stem’ [14], probably originated as a diminutive form of the now extinct stale ‘long handle’, a word distantly related to Greek steleá ‘handle’. The verb, ‘track stealthily’ [OE], goes back to a prehistoric Germanic *stalkōjan, which was formed from the same base as produced English steal. The sense ‘walk haughtily’, diametrically opposed to ‘track stealthily’, emerged in the 16th century.
[stalk etymology, stalk origin, 英语词源]
stalk (n.)youdaoicibaDictYouDict
"stem of a plant," early 14c., probably a diminutive (with -k suffix) of stale "one of the uprights of a ladder, handle, stalk," from Old English stalu "wooden part" (of a tool or instrument), from Proto-Germanic *stalla- (cognates: Old English steala "stalk, support," steall "place"), from PIE *stol-no-, suffixed form of *stol-, variant of root *stel- "to put, stand" (see stall (n.1)). Of similar structures in animals from 1826.
stalk (v.1)youdaoicibaDictYouDict
"pursue stealthily," Old English -stealcian, as in bestealcian "to steal along, walk warily," from Proto-Germanic *stalkon, frequentative of PIE *stel-, possibly a variant of *ster- (3) "to rob, steal" (see steal (v.)). Compare hark/hear, talk/tell). In another view the Old English word might be from a sense of stalk (v.1), influenced by stalk (n.). Meaning "harass obsessively" first recorded 1991. Related: Stalked; stalking.

A stalking-horse in literal use was a horse draped in trappings and trained to allow a fowler to conceal himself behind it to get within range of the game; figurative sense of "person who participates in a proceeding to disguise its real purpose" is recorded from 1610s.
stalk (v.2)youdaoicibaDictYouDict
"walk haughtily" (nearly the opposite meaning of stalk (v.1)), 1520s, perhaps from stalk (n.) with a notion of "long, awkward strides," or from Old English stealcung "a stalking, act of going stealthily," related to stealc "steep, lofty."