1.  eleven(n = noun.quantity) 11, xi - the cardinal number that is the sum of ten and one;
is a kind of large integer

2.  eleven(n = noun.group) football team - a team that plays football;
is a kind of squad, team
is a member of football league

   eleven(s = adj.all) 11, xi - being one more than ten;

   Ten and one added; as, eleven men. [1913 Webster]

1.  The sum of ten and one; eleven units or objects. [1913 Webster]

2.  A symbol representing eleven units, as 11 or xi. [1913 Webster]

3.  The eleven men selected to play on one side in a match, as the representatives of a club or a locality; as, the all-England eleven. [1913 Webster]

eleven, n. & adj.
--n.
1 one more than ten; the sum of six units and five units.
2 a symbol for this (11, xi, XI).
3 a size etc. denoted by eleven.
4 a set or team of eleven individuals.
5 the time of eleven o'clock (is it eleven yet?).
--adj. that amount to eleven.

Idiom:
eleven-plus esp. hist. (in the UK) an examination taken at the age of 11-12 to determine the type of secondary school a child should enter.

Etymology:
OE endleofon f. Gmc

N  deputy, substitute, vice, proxy, locum tenens, badli, delegate, representative, next friend, surrogate, secondary, regent, viceregent, vizier, minister, vicar, premier, chancellor, prefect, provost, warden, lieutenant, archon, consul, proconsul, viceroy, commissioner, Tsung-li Yamen, Wai Wu Pu, plenipotentiary, alter ego, team, eight, eleven, champion, acting, vice, vice regal, accredited to, in behalf of.

N  five, five, cinque, quint, quincux, six, half-a- dozen, half dozen, seven, eight, nine, three times three, dicker, ten, decade, eleven, twelve, dozen, thirteen, long dozen, baker's dozen, quintuplet, twenty, score, twenty-four, four and twenty, two dozen, twenty-five, five and twenty, quarter of a hundred, forty, two score, fifty, half a hundred, sixty, three score, seventy, three score and ten, eighty, four score, ninety, fourscore and ten, sestiad, hundred, centenary, hecatomb, century, hundredweight, cwt, one hundred and forty-four, gross, thousand, chiliad, millennium, thousand years, grand, myriad, ten thousand, ban, man, ten thousand years, banzai, lac, one hundred thousand, plum, million, thousand million, milliard, billion, trillion, five, quinary, quintuple, fifth, senary, sextuple, sixth, seventh, septuple, octuple, eighth, ninefold, ninth, tenfold, decimal, denary, decuple, tenth, eleventh, duodenary, duodenal, twelfth, in one's 'teens, thirteenth, vicesimal, vigesimal, twentieth, twenty-fourth, vicenary, vicennial, centuple, centuplicate, centennial, centenary, centurial, secular, hundredth, thousandth.