shadow n.

Middle English shadwe, from Old English sceadwe, sceaduwe "shade, the effect of interception of sunlight; dark image cast by someone or something when interposed between an object and a source of light," oblique cases ("to the," "from the," "of the," "in the") of sceadu (see shade (n.)). Shadow is to shade (n.) as meadow is to mead (n.2). Similar formation in Old Saxon skado, Middle Dutch schaeduwe, Dutch schaduw, Old High German scato, German schatten, Gothic skadus "shadow, shade."

From mid-13c. as "darkened area created by shadows, shade." From early 13c. in sense "anything unreal;" mid-14c. as "a ghost." Many senses are from the notion of "that which follows or attends a person." From late 14c. as "a foreshadowing, prefiguration." Meaning "imitation, copy" is from 1690s. Sense of "the faintest trace" is from 1580s; that of "a spy who follows" is from 1859. Many of the modern English senses also were in Latin umbra, Greek skia, along with that of "uninvited guest who an invited one brings with him."

As a designation of members of an opposition party chosen as counterparts of the government in power, it is recorded from 1906. Shadow of Death (c. 1200) translates Vulgate umbra mortis (Psalms xxiii.4, etc.), which translates Greek skia thanatou, itself perhaps a mistranslation of a Hebrew word for "intense darkness." In "Beowulf," Grendel is a sceadugenga, a shadow-goer, and another word for "darkness" is sceaduhelm. To be afraid of one's (own) shadow "be very timorous" is from 1580s.

Middle English schadowen, schadwen, Kentish ssedwi, "provide, cover, or overspread with shade, protect from the sun or other light" (mid-14c.), from late Old English sceadwian "to protect as with covering wings" (also see overshadow), from the root of shadow (n.). Similar formation in Old Saxon skadoian, Dutch schaduwen, Old High German scatewen, German (über)schatten.

From late 14c. as "cast a shadow over" (literal and figurative), from early 15c. as "mark (in illustration, etc.) with slight gradations of color or light." The meaning "to follow like a shadow" is attested once c. 1600 and not again until 1872. Related: Shadowed; shadowing.