Question: What is the origin of the word "Dyke"?
Although the origin of the word lesbian is pretty clear, the origin of the word dyke depends on your source. Here are some popular theories about the origin of the word dyke.
Answer: According to Fortune City, the word Dyke was possibly from Boudicca (Bou-dyke-ah), a Celtic queen who organized a revolt against the Roman Empire in 67 A.D. Boudicca was seen as a threat to the power structure. Later, as its connotation changed to refer to lesbians.
Wikipedia says, "The word dike appeared in 1710 in British newspaper stories about cross-dressing pirates Anne Bonny and Mary Read. One editorial euphemistically referred to their cross dressing with a French word, dike, which refers to men's clothing."
According to the Electric Pride website, one theory about the origin of the word "dyke" as an anti-lesbian slur suggests that "dyke" derived from the word "hermaphrodite."
GLSEN suggests the word dyke may have come from the colloquial "dike" meaning to overdress. To get "diked out" is similar to our usage of getting "decked out."