Synonyms for Diaphanous (same or very similar meaning)
WordNet sense 1 (so thin as to transmit light):
cobwebby, filmy, gauzy, gossamer, see-through, sheer, transparent, vaporous, gauze-like, vapourous
WordNet sense 2 (of relatively small extent from one surface to the opposite or in cross section):
thin
From the ODE community, based on WordNet
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