Synonyms for Three-ply:

adj.

triple (adjective)
threefold, ternary, triplicate, triple, Trebled.

n.

cellular, brushed, crisp, filmy, fibrous, creased, colorfast, Breathable, diaphanous, distressed. three-ply (noun)
thick.

Other synonyms:

Other relevant words:
filmy, thick.