[From the phrase (drink) hob or nob, (toast) one another alternately, from obsolete and dialectal hab nab, have or have not : probably Middle English habbe, have; see have + Middle English nabbe(contraction of ne habbe, have not : Old English ne, not; see not + habbe, have).]
Word History: Hobnobbing with our social betters can be a hit-or-miss proposition, a fact that has an etymological justification. The verb hobnob originally meant “to drink together” and occurred as a varying phrase, hob or nob, hob-a-nob, or hob and nob, the first of which is recorded in 1763. This phrasal form reflects the origins of the verb in similar phrases that were used when two people toasted each other. The phrases were probably so used because hob is a variant of hab and nob of nab, which are probably forms of have and its negative. In Middle English, for example, one finds the forms habbe, “to have,” and nabbe, “not to have.” Hab or nab, or simply hab nab, thus meant “get or lose, hit or miss,” and the variant hob-nob also meant “hit or miss.” Used in the drinking phrase, hob or nob probably meant “give or take” from a drinking situation hob nob spread to other forms of chumminess

Originally posted by MWoody:
Beasty Boy?

Beastie Boys lyrics for "Jimmy James"