To smooth or smoooth (or even smooooooth) is to drink alcohol, (preferably Beam's Choice bourbon, which brand has unfortunately become hard to find) with Bob Tucker and participate in the appropriate ceremony.
Even before his death, there were those who claimed that Tucker need not be physically present because, through the central mystery of "fan substantiation," whenever the ceremony is performed, Tucker is present.
The ceremony's leader starts by taking a sip of the booze straight from the bottle and hands it to the next participant. Once the sacred potion has been imbibed, you pass the bottle on to the next person and hold your hand out a bit above shoulder level. You must keep your arm in the air until everyone in the room has had a nip — at large room parties this can take a while. Once every fan present has swigged, the bottle then goes back to Tucker (or his surrogate) for a final slurp. Then all the imbibers simultaneously dip their arms in a graceful arc as they stretch out the o's while intoning, "Smoooooooooth!"
Tucker began using the shtick at cons in early 1950s. “I stole the Smooth routine from Red Skelton in a movie,” he said, the 1948 MGM musical Ziegfield Follies. “Skelton had only a cameo role; he appeared for about three to five minutes selling ‘Guzzlers Gin’ in a TV commercial. At the end of the commercial he is half drunk and sitting on the floor; he looks up at the camera, swings his arm and cries, ‘Drink Guzzlers Gin — it's smooth!’ ”
Teetotalers and those who fear con crud are permitted to participate by just taking a symbolic whiff of the bottle in lieu of drinking.