Synonyms for Wispy (same or very similar meaning)
WordNet sense 1 (thin and weak):
wisplike
WordNet sense 2 (lacking excess flesh):
lean, thin
WordNet sense 3 (lacking clarity or distinctness):
dim, faint, shadowy, vague
WordNet sense 4 (not clearly defined or easy to perceive or understand):
indistinct
From the ODE community, based on WordNet
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