From Longman Dictionary of Contemporary Englishdykedyke, dike /daɪk/ noun [countable] 1 TBTTWa wall or bank built to keep back water and prevent flooding2 SYINSULT taboo informal an offensive word for a lesbian (=woman who is sexually attracted to women). Do not use this word.3 especially British EnglishTECTB a narrow passage to carry water away SYN ditch
Examples from the Corpus
dyke• Their sheep-fanks and cattle-pounds spread away, across land rented from the inn-keeper, in a close mesh of stone dykes.• Its level rises slowly and the land behind the dykes sinks, but even more slowly.• Damage has extended into the dykes which run between the grazing marshes.Origin dyke 1. Old English dic “ditch, dike”2. (1900-2000) Probably from morphadyke “male and female person, homosexual” ((1900-2000)), from hermaphrodite 