eleventh (adj.) Look up eleventh at Dictionary.com
late 14c., eleventhe, superseding earlier ellefte (c.1300), enlefte (early 13c.), from Old English endleofta; see eleven + -th (1). Eleventh hour "last moment, just before it is too late" is in Old English, from the parable of the laborers in the vineyard (Matt. xx:1-16); as an adjective by 1829.