early 14c., "handful or bundle of hay, grass, etc.," used for burning or cleaning or as a cushion; perhaps from an unrecorded Old English word, cognate with Norwegian and Swedish visp "wisp," of unknown origin; sometimes said to be connected with whisk or with Middle Low German and Middle Dutch wispel "a measure of grain." Meaning "thin, filmy portion" first attested 1836.
also jack-o-lantern, jack-a-lantern, jackolantern, 1660s, "night-watchman;" 1670s as a local name for a will-o-the-wisp (Latin ignis fatuus), mainly attested in East Anglia but also in southwestern England. Literally "Jack of (with) the lantern;" see Jack + lantern. The extension to carved pumpkin lanterns is attested by 1834 in American English.
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<a href="https://www.etymonline.com/word/will-o'-the-wisp">Etymology of will-o'-the-wisp by etymonline</a>
Harper, D. (n.d.). Etymology of will-o'-the-wisp. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/will-o'-the-wisp