A salute is a sign of respect. A soldier may salute senior officers by raising a hand to his or her head, or you may informally salute a neighbor with a tip of your hat.
Salute often has a military context, whether used as a verb or a noun. When gladiators showed up for a day’s work at the Coliseum in Ancient Rome, they had to be prepared to die in battle for the entertainment of the emperor. Beforehand, they would address the emperor with the Latin words “morituri te salutant”, which means “Those of us who are about to die salute you.” Many centuries later, the heavy metal band AC/DC would change those words to a song with a much happier sentiment: “For those about to rock, we salute you.” Rock on.