moat
n. countablen. a deep, wide hole filled with water that goes around a castle to protect it. In business, it means a special advantage that keeps a company safe from its competitors.
n. a deep, wide ditch surrounding a fortified place, typically filled with water. In a commercial context, it refers to a sustainable competitive advantage that protects a company's market share from rivals.
The castle is protected by a deep, water-filled moat.
The company's strong brand name acts as a moat, making it difficult for new startups to compete.
Investors often look for companies with a wide economic moat, such as proprietary technology or high switching costs, to ensure long-term profitability in a crowded market.
From Middle English mote, from Old French mote (“mound, embankment”); compared also to Old French motte (“hillock, lump, clod, turf”), from Medieval Latin mota (“a mound, hill”), of Germanic origin, perhaps via Frankish mot, motta (“mud, peat, bog, turf”), from Proto-Germanic mutô, mudraz, muþraz (“dirt, filth, mud, swamp”), from Proto-Indo-European (s)mut- (“dark, dirty”). Cognate with Alemannic German Mott, Mutte (“peat, turf”), Bavarian Mott (“peat, turf”), dialectal Dutch mot (“dust, fine sand”), Saterland Frisian mut (“grit, litter, humus”), Swedish muta (“to drizzle”), Old English mot (“speck, particle”). More at mote, mud, smut. As term for a business strategy, popularized by American investor Warren Buffett.
In modern business English, often used metaphorically with the adjectives 'wide' or 'narrow'.