a yellow streak
Meaning: If someone has a yellow streak, they can sometimes act in a cowardly way and not be very brave.
- Some people say Jimmy's got a yellow streak a mile wide, but I've never seen anything in him except courage and bravery.
- Monty says he likes his yellow streak because it keeps him out of trouble. He never gets into fights or has accidents because he's so scared of getting hurt.
You can see Bob's yellow streak when another player is running straight at him and Bob