NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting any projectile in flight.
TBH usually means To Be Honest, but it can also mean Honest Opinion. To Be Honest was the original meaning of TBH, but nowadays it often just means Honest Opinion or Honest Comment. Of note, TBH was originally used with a blunt or slightly antagonistic statement to suggest the statement derived from sincerity.
TSH is the abbreviation for thyroid stimulating hormone. TSH is a hormone that your pituitary gland produces; the production of TSH sets off a chain reaction and lets your thyroid know it's time to make its own hormones, called T3 and T4.