Dyke

1. a long wall or embankment built to prevent flooding from the sea.
2. a ditch or watercourse.
3. an intrusion of igneous rock cutting across existing strata.
4. a toilet.

1. provide (land) with a wall or embankment to prevent flooding.

   they dyked the marshland along the rivers to provide pasture in summer

   the fertility of those dyked lands was unrivalled

Middle English (denoting a trench or ditch): from Old Norse dík, related to ditch. dyke¹ (sense 1 of the noun) has been influenced by Middle Low German dīk ‘dam’ and Middle Dutch dijc ‘ditch, dam’.

noun

a lesbian.

1930s: origin uncertain: probably from bull dyke.