vaporous

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"

resembling or characteristic of vapor; "vaporous clouds"

filled with vapor; "miasmic jungles"; "a vaporous bog"