From The Collaborative International Dictionary of English v.0.48 [gcide]:
Vaporous \Va"por*ous\ (v[=a]"p[~e]r*[u^]s`), a. [L. vaporosus:
cf. F. vaporeux.]
[1913 Webster]
1. Having the form or nature of vapor. --Holland.
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2. Full of vapors or exhalations. --Shak.
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The warmer and more vaporous air of the valleys.
--Derham.
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3. Producing vapors; hence, windy; flatulent. --Bacon.
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The food which is most vaporous and perspirable is
the most easily digested. --Arbuthnot.
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4. Unreal; unsubstantial; vain; whimsical.
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Such vaporous speculations were inevitable.
--Carlyle.
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From WordNet (r) 3.0 (2006) [wn]:
vaporous
adj 1: so thin as to transmit light; "a hat with a diaphanous
veil"; "filmy wings of a moth"; "gauzy clouds of
dandelion down"; "gossamer cobwebs"; "sheer silk
stockings"; "transparent chiffon"; "vaporous silks" [syn:
diaphanous, filmy, gauzy, gauze-like, gossamer,
see-through, sheer, transparent, vaporous,
vapourous, cobwebby]
2: resembling or characteristic of vapor; "vaporous clouds"
[syn: vaporific, vapourific, vaporish, vapourish,
vaporous, vapourous]
3: filled with vapor; "miasmic jungles"; "a vaporous bog" [syn:
miasmal, miasmic, vaporous, vapourous]