When is a verb not a verb? Sometimes a verb form ending in
ing can function as a noun ("Urethaning is the next step"). I think this is what is termed a gerund.
But in this case, it seems that people sometimes say
urethaned, as well as
urethaning, so
urethane is sometimes treated as a verb. A couple of examples (grammatical analysis left up to the reader). First, from
Log Homes Design Ideas magazine:
...as well as the other areas of interior and exterior finish, such as paint staining, urethaning and all the other duties and jobs that can make one's back sore.
And a
urethaned example, from askthebuilder.com:
Don't even think of installing one piece of wood until you have pre-stained and urethaned every piece of wood you will need for the job.
I didn't see
urethaning listed in any dictionary, and
urethane as a verb is noted only in the Canadian Oxford: "coat with a polyurethane finish". Nevertheless it is a fairly standard construction, whose meaning is obvious - transparent, one might say.
I'll add
urethaning and
urethaned as
common RARE words.