Cleave is its own antonym — two unrelated Old English verbs (to split / to cling) collided into one word, creating English's most famous self-contradiction.
To split or divide by force. Paradoxically, also to cling or adhere firmly. One of English's most famous contronyms — a word with two opposite meanings.
Two separate Old English verbs have merged into one spelling: clēofan (to split, from Proto-Germanic *kleubaną) and clifian (to stick, cling, from Proto-Germanic *klibjaną). These are unrelated words that converged by phonetic accident Key roots: *kleubaną (Proto-Germanic: "to split, cleave"), *klibjaną (Proto-Germanic: "to stick, adhere").
Cleave is English's most famous contronym — a word that is its own opposite. To cleave means both to split apart AND to cling together. This paradox exists because two completely unrelated Old English verbs (clēofan, to split; clifian, to cling) converged into the same modern spelling through sound changes over centuries. Other English contronyms include "sanction" (to permit / to punish), "dust