A type of clear plastic that looks like glass.
Plexiglass is often used instead of glass because it is strong and doesn't break easily.
Examples:
The window is made of plexiglass.
I can see through the plexiglass.
He uses plexiglass to cover the table.
The plexiglass makes the picture look funny.
The whole house is made of plexiglass!
I want to build a castle out of plexiglass.