What is the meaning of the word "hello"

It's just a greeting, meaning u acknowledge one's presence with you...politely...

Alexander Graham Bell gave us the telephone, and also the greeting hello in 1876. The french in the Middle Ages used Ho là! which meant meant both "stop" and "pay attention" Well long distance telephones came into play, there was halooo in 1568 and hullo in 1707. Varieants continued but resulted in the modern hello.