Any object (toy) that gives pleasure
upon being squeezed.
Squeeze toys come in many different varieties including foam, plastic, rubber, and sand or baking soda filled balloon.
Squeeze toys that squeak are usually classed under pet toys, however certain kinds such as the proverbial 'rubber duckie' are more suitable for children.
Sometimes the foam, or sand filled balloon variety are given away at technical conventions by companies interested in having you squeeze their logo in times of stress.
You can make your own squeeze toy by filling a balloon with baking soda and tying it at the top.