fellatio
Concise Oxford English Dictionary © 2008 Oxford University Press:
fellatio /fɛˈleɪʃɪəʊ, -ˈlɑːt-/
▶noun oral stimulation of a man's penis.
– derivatives
fellate verb,
fellator /fɛˈleɪtə/ noun.
fellate verb,
fellator /fɛˈleɪtə/ noun.
– origin C19: mod. L., from L. fellare ‘to suck’.
'fellatio' also found in these Oxford entries:

