Synonyms of eavesdropper

1 Syllable
prier, sleuth, pryer, snoop
2 Syllables
trackers, ropers, butt-in, snooped, shamus, snooper, shoofly, roper, slewfoot, snoopers, tracker, hearer, ferret
3 Syllables
newsmonger, auditor, pragmatist
4 Syllables
busybody, wiretapper, detective