No, it is not. It is a verb form (present participle of to ply) that can be used as a noun, but uncharacteristically not as an adjective.
Plying with the best bus i have ever seen.
i was playing
its plying tennis
plying cricket
Phoenix Suns
Keeps you fit and it can make you lots of $$$
Barber
A mariner, which led to him exploring in the proces of plying his trade.
fairness is about not being boosy but to play fair or take turns and not plying favorites
Don't play on laptop.
well i have some and i believe they are mating or just plying
She first learned how to play the Guitar when she was 11 years old.