A phrase meaning that the speaker intends to add the listener to a list, or make an appointment for the listener to attend a meeting at a later time.

(Pencil, a noun, is being used as a verb for the action associated with it.)
Fred: I need help with my homework.
Daphne: I'm not free until 6.30. I'll pencil you in for then if that's OK.
Fred: It's a date.
by phantom oddity May 20, 2004
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To make definite plans to meet with someone. As in writing your name in an appointment book.
I'm free Thursday afternoon, so I'll pencil you in.
by jafo May 20, 2004
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To sexually assult/stimulate someone with a pencil, usually rubber end first for safety.
Oi, come here you silly slag... I'll pencil you in!
by Horny B April 27, 2008
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To pencil someone into a schedule but using a light amount of pressure. This way, as you know they will always cancel, when you erase, there is no visual indent of their name in your schedule.
Guy: sorry I keep cancelling on you, would you like to go to the cinema on Friday?

Girl: yes, I'll lightly pencil you in.
Guy cancels
Girl to friend: I am glad I only lightly penciled him in, as there is no indent to remind me that he cancelled AGAIN!
by Lightly pencilling January 4, 2014
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1. Having no intention of following thru on a date or promise

2. A sarcastic way of accepting a date.

3. Accepting a date only to mock the requester.
Raul: Hi Jess, will you go to Hooters with me on Friday?
Jess: Sure, let me just pencil you into my Blackberry!
Raul: Really?!
Jess: Ew, no!
by Dayznout February 28, 2012
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It literally means that someone will give you the details of something, but is usually just someone trying to give you the runaround.
"What happened with you and your girlfriend?"
"I'll pencil you in later."
by Jessica May 20, 2004
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