gull

Etymology 1

From Middle English gulle, from a Brythonic language, from Proto-Brythonic *gwuɨlann, from Proto-Celtic *wēlannā (“seagull”). Cognate with Welsh gwylan, Cornish goolan, Breton gouelan, Old Irish faílenn, Scottish Gaelic faoileag. Compare French goéland, a borrowing from Breton.

noun

1. A seabird of the genus Larus or of the family Laridae.
   The tide was out, and we drew up amid the strong bracing smell of seaweed, with gulls screeching, wheeling around, and gliding on the wind. 1947 January and February, O. S. Nock, “"The Aberdonian" in Wartime”, in Railway Magazine, page 8
2. Any of various pierid butterflies of the genus Cepora.

Etymology 2

Perhaps from an obsolete term gull (“swallow”).

noun

1. (slang) A cheating trick; a fraud.
2. One easily cheated; a dupe.
3. (obsolete, Oxford University slang) A swindler or trickster.
   You'll excuse me, sir, but as you are fresh, take care to avoid the gulls; they fly about here in large flocks, I assure you, and do no little mischief at times." "I never understood that gulls were birds of prey," said I.—"Only in Oxford, sir; and here, I assure you, they bite like hawks, and pick many a poor young gentleman as bare before his three years are expired, as the crows would a dead sheep upon a common. […]" 1825, Bernard Blackmantle, The English Spy

verb

1. To deceive or cheat.
   The vulgar, gulled into rebellion, armed. 1660, John Dryden, Astraea Redux
   I'm not gulling him for the emperor's service. c. 1798, Samuel Taylor Coleridge, Wallenstein
   […] speak your curses out Against me, who would sooner crush and grind A brace of toads, than league with them to oppress An innocent lady, gull an Emperor […] 1819, John Keats, Otho the Great, act IV, scene I, verse 162-165
   She has done these things before and remembers now that she is good at them, often steadier than the men. In Berlin when Jack needed a spare girl Mary had kept watch, gulled room keys out of concierges, replaced stolen documents in dangerous desks, driven scared Joes to safe flats. 1986, John le Carré, A Perfect Spy
2. (US, slang) To mislead.
3. (US, slang) To trick and defraud.