moat

Etymology

From Middle English mote, from Old French mote (“mound, embankment”); compare also 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.

noun

1. A deep, wide defensive ditch, normally filled with water, surrounding a fortified habitation.
2. (business, figurative) An aspect of a business which makes it more "defensible" from competitors, because of the nature of its products, services or franchise or for some other reason.
   No matter how good your company's product is or how quickly the industry is growing, if there is no moat, competitors will invade your castle and burn it down. 2013, John Mauldin, Jonathan Tepper, Code Red: How to Protect Your Savings From the Coming Crisis, John Wiley & Sons
   “I think ‘moats’ are lame,” Mr. Musk had said during a Tesla earnings call. It was a criticism of an economic principle that Mr. Buffett had coined in 1999 and that has become something of a mantra for his faithful: Invest in businesses “that have wide, sustainable moats around them.” 2018-05-07, Andrew Ross Sorkin, quoting Elon Musk, “Elon Musk Wants to Fill Warren Buffett’s ‘Moat’ With Candy, but It Still Holds Water”, in The New York Times, →ISSN
3. A circular lowland between a resurgent dome and the walls of the caldera surrounding it.
4. (meteorology) A clear ring outside the eyewall of a tropical cyclone.
5. (obsolete) A hill or mound.

verb

1. (transitive) To surround with a moat.