The work, duties, or practice of being a butler; the action or process of serving as a butler.
From butler plus the gerund suffix -ing, which converts verbs to nouns describing the action. This nominalization became common in English for describing occupational activities.
Butling required specific training in hierarchy, discretion, and technique—a good butler had to know which fork to serve with, how to remain invisible while present, and never to gossip about the family's affairs.
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