By themselves...no. "Video clips of naked college students"...Yeah, probably lol It all depends upon how they are used, what context, etc.
Like the person above posted, if it's the word Video Clips or Movie Clips without being followed by an 'x' rated term then it's not against the T.O.S.
I don't think video clips would be against TOS since most clips would be completely legal. unlike mp3 downloads.
There are some words that supposedly trigger Adsense to show only PSA's on your site or get your site banned if the content of the site is against TOS. Most of them "bad words" related to pornography or violence, as I recall.