Oh, I think I did mess up here. I was thinking in terms of 'spy' as an independent adjective as in 'spy glass', 'spy fiction', and 'spy story'--but, in having looked up the terms on Onelook.com, I see that these are nouns unto themselves. But, then again, if I were to characterize a person as wearing an enormous coat, one large enough to weather any storm, a virtual spy coat--wouldn't you visualize Columbo (or Colombo, or whoever that person was I never did see except in commercials (I swear)?

Anyway, I back out on 'spy' as an adjective since apparently no dictionary will back me up.

However, I would like to point out [I thought of this driving to work early this morning] that 'ing' verbs give us a huge selection of v/n/a conformations through participles and gerunds, as in:

I am swimming;
Swimming is my favorite morning activity;
Elise, the swimming champion, truly displayed more humility than anyone else in the room.

And the list of 'ing' words, (v./a./n.-gerunds) is perhaps endless if we go about verbing and nouning anything we can think of doing, from oohing to ahing.