Pajaso means about a great handjob and it's an augmentative of Paja meaning the same as handjob Some synonyms, words or similar expressions can be paja, masturbacion, vladimir una paja y a dormir, jalarse el ganzo, jalarsela, chaqueta, chaquetearsela, jaladota
"At night I had the best handjob ever - Por la noche tuve la mejor paja del mundo - Anoche me hice un pajaso - At night I had a great handjob"