To commit acquaintance rape against someone. From an onomatopoeic usage of GHB, the date rape drug, "to GHB someone" becomes "to ghoob someone."
I spiked my date's drink last night, and after she passed out, I ghoobed her.

OR

I'm busy tonight. I'm going ghoobing.
by The Enormous Talking Onion February 9, 2004
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