Dumbbell (noun)

1. A piece of gym equipment consisting of a short bar with weights at either end, used for weight training.
2. A person who is not very intelligent or is unable to speak.

Origin:

From dumb ("mute") + bell ("bell"), so called because the original weights were in the shape of a bell with no clapper.

Examples:

1. He picked up the dumbbell and began his weightlifting routine.
2. The personal trainer suggested using dumbbells to target specific muscle groups.
3. He was considered a dumbbell by his classmates because of his lack of intelligence.
4. The patient was diagnosed as dumbbell, unable to speak or communicate.
5. She thought of him as a dumbbell because of his lack of social skills.