The Ferengi practice of massaging the lobes, which are among the most sensitive parts of a Ferengi's body, enjoyed as an intimate pleasure and occasionally exploited by others.
Oo-mox is the stroking or massaging of a Ferengi's ears. The lobes are an erogenous zone, and Ferengi males in particular are almost helpless while receiving it.
The term is first heard in Ménage à Troi. Held prisoner by DaiMon Tog, Lwaxana Troi distracts him with oo-mox in an attempt to help Deanna Troi and William Riker escape. On Deep Space Nine it is mentioned often in connection with Quark, whose weakness for it others use against him.
In Rules of Acquisition the waiter Pel, a Ferengi female in disguise, shows affection for Quark in this way. Leeta offers it to Rom in the later seasons. The custom is usually played for comedy, but it also shows how much Ferengi culture centres on the ear.