Synonyms for Trailing:

adj.

•following (adjective)
consequent, outcome, following, hunting, lagging, closing, tracking, pursuing, ensuing, descending, posterior.
•lagging behind (adjective)
creeping, dawdling, falling behind, behind, lagging, crawling.

n.

arboreal, bushy, bare, barren, biennial, androgynous, aromatic, aquatic, algal. •trailing (noun)
tracking, down, behind.

v.

•following (verb)
lagging, resulting, succeeding, descending, ensuing.
•hanging (verb)
drooping, nodding, Draggling, lolling, Draping, dangling, swinging, swaying, hanging, Bobbing, sagging.
•pursuing (verb)
tailing, seeking, pursuing, questing, tracking, sleuthing, Endeavoring, Aiming, following, striving, searching, aspiring, Harrying, stalking, hunting, dogging, Chasing, undertaking, Intending.
•smelling (verb)
stinking, exhaling, Perfuming, smelling, Emanating, breathing, Whiffing.

Other synonyms:

creeping. •behind
behind.
•Other relevant words:
barren, biennial, aquatic, down, algal, androgynous, dawdling, bushy, arboreal, losing, aromatic, crawling, bare, creeping, endmost, behind.

Usage examples for trailing

1. Canes slender, numerous, long, slightly trailing – Manual of American Grape-Growing by U. P. Hedrick

2. I hadn't thought they'd carry their watching and trailing of us so far. – The Million-Dollar Suitcase by Alice MacGowan Perry Newberry

3. We are not trailing a criminal. – Sight Unseen by Mary Roberts Rinehart