$10 is a dime of anything. The only dealer I had who did dimes was really good at math. So I did the math while he weighed it and it always came up nice.
If your dealer isn't talking to you about grams... 1. He's probably too stupid to know what a gram is 2. He's selling you shitty ass weed 3. You are an idiot for ever considering to buy weed from them 4. You're getting anal raped.
What ever happened to that sticky that said how many grams and shit were in everything. I showed it to a friend and they were surprised there were 3.5 in an 1/8. They were on friend probation for a week.
Or could be slang for "mutually we know how much weed is worth, we're mature enough to not be ripping people off/getting ripped off and I can't be fucked to say 'can I have one point seven grams please?' so I ask for a tens" I don't always expect my product to be weighed in front of me because I don't deal with fuckheads, I can trust people I get smoke from. Half of them wouldn't sell me a ten draw though even if I wanted one..