Shadowing

n.	1.	Shade, or gradation of light and color; shading.
	2.	A faint representation; an adumbration. There are . . . in savage theology shadowings, quaint or majestic, of the conception of a Supreme Deity. - Tylor.

Noun	1.	shadowing - the act of following someone secretly Synonyms: tailing
Adj.	1.	shadowing - following surreptitiously; keeping under surveillance; "always on guard against shadowing submarines" Synonyms: tailing

shadowing - aliasing

ambuscade, ambush, ambushment, blackening, blind, blocking the light, booby trap, bugging, chase, chasing, cloak-and-dagger work, clouding, counterespionage, counterintelligence, darkening, dimming, dogging, eclipsing, electronic surveillance, espial, espionage, extinguishment, follow, follow-up, following, heeling, hounding, hue and cry, hunting, intelligence, intelligence work, lurking hole, military intelligence, obfuscation, obnubilation, obscuration, obscurement, observation, obumbration, occulting, overcast, overclouding, overshading, overshadowing, overshadowment, prosecution, pursual, pursuance, pursuing, pursuit, quest, searching, secret police, secret service, seeking, sequel, sequence, series, shading, spying, stakeout, stalking, stalking-horse, surveillance, tailing, tracking, tracking down, trailing, trap, wiretap, wiretapping