Definition of "XO"

XO

adjective
not comparable
1. Initialism of extra old; a grade of premium cognac that has been aged in barrels for more than 6.5 years.
noun
plural XOs
1. (military, nautical) Initialism of executive officer.
noun
plural XOs
1. Alternative letter-case form of xo (“hugs and kisses”)
  Quotations
  Looking out on the substitute scene / Still going strong / XO, Mom
  1998, Elliott Smith (lyrics and music), “Waltz #2 (XO)”, in XO