I came across this line in the book Ship of Theseus(p.14):
It's just an homage to his writing.
（the hand-written notes filling the book's margins are printed and an inseparable part of the book.）
I've never seen the word "homage" being used as a countable noun before, and having got an "an" before it?
Isn't it wrong to use the word "homage" as a countable noun?