The noun shadow has 9 senses (first 6 from tagged texts)
1. (17) shadow -- (shade within clear boundaries)
2. (8) darkness, dark, shadow -- (an unilluminated area; "he moved off into the darkness")
3. (3) apparition, phantom, phantasm, phantasma, fantasm, shadow -- (something existing in perception only; "a ghostly apparition at midnight")
4. (1) shadow -- (a premonition of something adverse; "a shadow over his happiness")
5. (1) trace, vestige, tincture, shadow -- (an indication that something has been present; "there wasn't a trace of evidence for the claim"; "a tincture of condescension")
6. (1) shadow -- (refuge from danger or observation; "he felt secure in his father's shadow")
7. shadow -- (a dominating and pervasive presence; "he received little recognition working in the shadow of his father")
8. tail, shadow, shadower -- (a spy employed to follow someone and report their movements)
9. shadow -- (an inseparable companion; "the poor child was his mother's shadow")
Overview of verb shadow
The verb shadow has 3 senses (first 1 from tagged texts)
1. (3) shadow -- (follow, usually without the person's knowledge; "The police are shadowing her")
2. shadow, shade, shade off -- (cast a shadow over)
3. shadow, overshadow, dwarf -- (make appear small by comparison; "This year's debt dwarves that of last year")