"cleave \kleev\ , verb:
1. To adhere closely; stick; cling.
2. To remain faithful.
3. To split or divide by or as if by a cutting blow, especially along a natural line of division, as the grain of wood.
4. To make by or as if by cutting.
5. To penetrate or pass through (air, water, etc.).
6. To cut off; sever.
7. To part or split, especially along a natural line of division.
8. To penetrate or advance by or as if by cutting."
Dictionary.com
This word has always bothered me because it seems to be it’s own opposite. :(