The terms Hey and Hello put together for a casual effect! It's useful in IM and is unique.
Dara: Heylo!
Dara: How are ya?
UrbDicRdr: I'm cool, thx. Heylo to you too.
by Darathinas March 13, 2006
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Hey and Hello all in one, a good way to greet informally!
Often used in two very distinct syllables, for effect, such as:

"Heylo! (Heyy-loh) What's up?"
by ready2rock April 07, 2008
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a combination of hey and hello

...well, what did you expect it to be??
sam: heylo
marc: hi
by mister fluffy penguin man December 29, 2010
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an angelic way of saying hello... comonly used in slang conversations :P
heylo motherfucker!!!
by lenny April 05, 2004
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The "lift" you get from consuming marijuana/cannabis/weed or vaping cannabis extracts. Popularized by Heylo Cannabis. heylocannabis.com
Girl, I can see your heylo. You have any to share?
by 710vaporco2 September 30, 2017
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