From WordNet (r) 3.0 (2006):
tab
n 1: the bill in a restaurant; "he asked the waiter for the
check" [syn: check, chit, tab]
2: sensationalist journalism [syn: yellow journalism,
tabloid, tab]
3: the key on a typewriter or a word processor that causes a
tabulation [syn: tab key, tab]
4: a short strip of material attached to or projecting from
something in order to facilitate opening or identifying or
handling it; "pull the tab to open the can"; "files with a
red tab will be stored separately"; "the collar has a tab
with a button hole"; "the filing cards were organized by
cards having indexed tabs"
5: a dose of medicine in the form of a small pellet [syn:
pill, lozenge, tablet, tab]