[Useless]

When in doubt, search for an authoritative reference.
George Carlin:
Cocksucker is a compound word and neither half of that is really dirty. The word -- the half sucker that's merely suggestive and the word cock is a half-way dirty word, 50% dirty -- dirty half the time, depending on what you mean by it. Uh, remember when you first heard it, like in 6th grade, you used to giggle. And the cock crowed three times, the cock -- three times. It's in the Bible, cock in the Bible.

I always use 'cocksucker'.