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Hobnob

To work together on friendly terms
...also to drink together:

"Have another glass!"
"With you hob and nob" returned the sergeant.
(- Charles Dickens, Great Expectations)

merged from hob and nob ("give" and "take"),
derived from the earlier hab or nab lit. have or have not,
from OE habban to have + nabban not to have (ne not + habban), circa 1600

Though it turns out to be a form of circular reference, this suggestion was treated here.