Definition: A weak or fearful person; someone who lacks courage. Slang
Example:
1) I was too much of a wimp to play sports in high school.
2) Don’t be such a wimp — riding a bike can’t hurt you!
Etymology: A ‘whimper’ is a small cry of pain or fear. Someone who whimpers a lot and is afraid of getting hurt is a thus a ‘wimp’.
Synonyms: sissy, wuss, chicken.