Other forms: immovables
Immovable things can't be budged. While you can move a bicycle or a grocery cart or a balloon, a cement park bench is immovable.
Many things are immovable because they're made to be that way: a car is designed to be immovable when it's shifted into "park," or when the emergency brake is pulled. Other things are only occasionally immovable, like your stubborn dog who becomes immovable every time you try to take him for a walk in the rain, rooted adamantly in the doorway as you pull on his leash.