A person who has difficulty controlling their muscles and movements.
This word can be mean and hurtful. It is better to use other words like 'clumsy' or 'awkward'.
Examples:
He walks in a spastic way.
She has a spastic arm.
The spastic boy can't run very well.
The cat looks spastic when it tries to catch a bug.
The robot moved in a spastic manner, jerking and shaking.
The spastic girl can't play ball like the other kids.