It's called "Newton's Cradle".
It's also known as "Balance Balls", "Newton's Pendulum", and "Newton's Balls"
This toy demonstrates the law of conservation of momentum.
you should call someone
Usually, what you would call a thing to but other things in is a container. It contains the items you wish to put in to, so they will not escape and run wild through your home like savages in the jungle. :)
odd balls
Yes, no other umpire can overrule a ball-strike call.
you call it hail
A Woman.
Call my girlfriend over.
A juggler.
balls of fire
You can't call her. Her mobile number and other personal details are private.
Ecosystem
servant