An alternative to spelling the word "Hey". Invented by a kindergartener who was falsely deemed as a terrible speller (received a 50 on his latest spelling test). Widely mistaken as a plant or grass used to feed animals.
"Hey Chuck, pass me that barrel of hay over there, will ya?"
"It's pronounced 'hay', you dope."
"What's the difference?"
"Use 'hay' next time you fucking idiot!"
Note: We have just been informed that Chuck is the same kindergartner that used this word, he was later put into an insane asylum. Tell him I said "Hay" for me.