Wordnet 3.0
NOUN (1)
1. 
 a lover who gently fondles and caresses the loved one; 
- Example: "they are heavy petters"[syn: petter, fondler]
WordNet (r) 3.0 (2006):
petter
    n 1: a lover who gently fondles and caresses the loved one;
         "they are heavy petters" [syn: petter, fondler]