What does the word stud mean?

Usage examples for stud

  1. " Please, Mrs. Putchy, send at once to the nearest hosier's and buy me a plain collar- stud, and kindly ask Mary to get back as quickly as possible. – The Mysterious Shin Shira by George Edward Farrow
  2. Then, before he pressed the stud, he looked at Cardon curiously. – Null-ABC by Henry Beam Piper and John Joseph McGuire
  3. Ralph the heir had bought some of his uncle's horses, and had commenced hunting with the hounds around him; though he had not as yet withdrawn his stud from the Moonbeam. – Ralph the Heir by Anthony Trollope