Getting to third base is the most ambiguous stage of high-school heterosexual interaction. The definition really depends on how far the boy goes: is it an intermediate stage followed by going all the way, or is it the final stage of making out? (everything that follows is from the boy's perspective) When I was a kid (mid-70s) it meant groping skin-to-skin instead of through the clothes. Today it's gone farther: "getting to third" implies that you eventually squirted; "I got as far as third" means that you didn't do it inside her (hand job, blow job, dry-hump, just lose it while making out, etc.). If you go all the way, it doesn't really matter when you got to third.
"How far did you go?"
"Third base, dude! She wouldn't drop her panties, but we kept at it until I spooged my boxers."
by e-boy February 19, 2007
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In relationship/sexual terminology, this is the Stage in dating where while making out or making love, the couple advances by heavy petting and touching, while potentially removing a few articles of clothing.
This can include touching of the woman's bare legs, breasts, and hips. This can lead to the touching of private-areas.

For some, this can lead to stimulating one-another's private regions by Touch.
In more hardcore culture, this can also include oral sex or fingering. See also Mutual Masturbation
"I want to go and play. But Mommy says, that Angela is busy on the other side of the Hill. And that I have to wait until they leave. My friend Sam says they are on Third Base."
by SMX February 8, 2013
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The place at a black jack table that corresponds with third base on a baseball diamond. A good place to be because you never get screwed up by squares taking or not taking cards other than "by the book."
Thank god i was at third base all night because there were 4 yahoos at my table taking cards on 17
by Kreskin January 22, 2007
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Oral ( eating a girl out, blow job). Some people think fingering and handjobs are third but no they aren't, that's second. Get your bases right ;)
She wen't down on me. Best third base I've ever had.
by Sexxx July 18, 2005
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This is the third step to a relationship where heavy petting and feeling up occurs.

Ex. touching ones private through clothing or direct contact
Oh wow me and Molly got to third base the other day, it was great.
by NekoNeoNano June 27, 2015
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