A cricket team of eleven players. Hence first eleven - the team of best cricket players (at a school), second eleven - the "B" team, etc.
A football team of eleven players; the starting lineup.
Used instead of ! to amplify an exclamation, imitating someone who forgets to press the shift key while typing exclamation points.
A number off the charts of a hypothetical scale of one to ten.
The cardinal number occurring after ten and before twelve. Represented as 11 in Arabic digits.