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5. LMK
1. Let Me Know
2. Lick My Knuts
"Just LMK if I can help you out"
-or-
"Just LMK if that will help"
by anonymous Sep 30, 2003 add a video
1. LMK
Let me know
What do you think? LMK...
by anonymous Oct 1, 2003 add a video
2. LMK
It simply means "let me know." Or get back to me with answer.

If it already formally exists, I don't know, but I started using it in my e-mails in the '90s for convenience. Today, someone responded "OH!!!!!!" after I replied to his "what's the meaning of that" e-mail. So, there you have it.
In e-mail commonly, consider for example:
1) If you need anything, LMK.
2) What're you guys doing tonight? LMK.
3. LMK
Means Lick My Kitten, Kitten being slang for the female genetalia, this term would be used in the same context by a female that a male world use the phrase "Suck my dick" in
Girl: LMK
Guy: what's that mean
Girl: lick my kitten
4. LMK
1. Launched my Kitten

2. Lick my Klit
What did you do today?
LMK!

Hey could you LMK?
6. LMK
Lets make Kids Let's Make Kids
Username: I just got a million dollars.

James: LMK! LMK!
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