/keuh loh"dee euhn/ , n.
a yellowish, viscous, highly flammable solution of pyroxylin in ether and alcohol: used in the manufacture of photographic film, in engraving and lithography, and in medicine chiefly for cementing dressings and sealing wounds.
[ 1850-55; alter. of NL collodium kollód ( es ) glutinous ( kóll ( a ) glue + -odes -ODE 1 ) + -ium -IUM ]