adj

• (not comparable) Without a corresponding mate in a pair or set; unmatched; (of a pair or set) mismatched.
  "Optimistically, he had a corner of a drawer for odd socks."
• (not comparable) Left over, remaining after the rest have been paired or grouped.
  "I'm the odd one out."
• (not comparable) Left over or remaining (as a small amount) after counting, payment, etc.
  ""Here, I have some odd change that should make things easier." As Tish turned and reached for the cigarettes, Eric took some loose coins from his pocket and placed the change from the twenty into his other pocket."
• (not comparable) Scattered; occasional, infrequent; not forming part of a set or pattern.
  "I don't speak Latin well, so in hearing a dissertation in Latin, I would only be able to make out the odd word of it."

noun

• (informal) Something left over, not forming part of a set.
  "I’ve got three complete sets of these trading cards for sale, plus a few dozen odds."
• (mathematics, diminutive) An odd number.
  "So let’s see. There are two evens here and three odds."

noun

• (computing) Initialism of optical disc drive.