Other forms: fathers; fathered; fathering
The verb father means to make children. If your dog, Tramp, fathers three puppies with the neighbor's dog, Lady, he is their father.
A father is a male parent. Everyone has a biological father, even if they're not raised by him. You might call your father Dad, Daddy, Papa, Pops, or even Father. A man who helped found something, or invent it, can be called the father of that entity or invention. George Washington is considered a father of the United States, and Alexander Graham Bell is often referred to as the father of the telephone.