It can be a synonym for ‘seriously’ or ‘for real’ depending on the situation.
i mean it... HEAVY

Person 1: ‘Paul smells init?’
Person 2: ‘Heavy
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"serious," NOT an indication that something is wrong with the earth's gravitaional pull in the year 1985.
by Flux C. July 16, 2003
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1. (adj.) Very massive; fat; weighs a lot.

2. (adj.) Serious and intense.

3. (adj.) Hardcore, brutal, raw.

4. (noun) A tough guy.

5. (adj.) Carrying a weapon, most likely a gun.
John: Did you see that guy? He must have weighed 400 pounds?!
Jane: Yeah, I know, he was really heavy.

John: Last night, my mom died.

Steve: Man, that's heavy.

Whitechapel is heavy.

The club was having problems with riff-raff, so they hired a couple heavies to bounce.

The other side came heavy to the fight, so we beat it outta there pretty quick.
by agrainofsalt July 6, 2009
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The state one finds themselves in when taking benzodiazepines.
I was heavy as fuck after I took those xanax.
by kittensandjesus August 9, 2014
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A large muscular man employed to menace or intimidate, or as a nightclub bouncer. (UK slang)
The gangster was annoyed, so he sent a couple of heavies round.
by retrocool December 12, 2003
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to carry a gun or some other type of firearm
don't mess with him, he came heavy
by tommy August 13, 2003
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To be carrying a firearm. Used most often by Italian mafiosi, but sometimes used by african-american "gangstas." The equivalent of "packing heat" or "coming hot".
I went heavy, but I didn't even need it to punk those bitches out.
by Mertens21 January 11, 2007
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