1 definition by Jack Mahogov
A (generally) teen-age boy who spends the majority of his time masturbating into a tube sock. Sock fillers tend to be socially awkward, often standing slack-jawed while in the presence of their female classmates.
"As the girls' P.E. class ran past, a large number of sock fillers began to shift uncomfortably and mumble to each other."
by Jack Mahogov November 14, 2012