Green’s Dictionary of Slang

a flatterer, a sycophant; a tale-bearer, a tell-tale; occas. used as v. (see cits. 1642 and 1740).

c.1204		Richard of Devizes Chronicles of Crusades n.p.: London [...] Garamates, pickthanks, catamites, effeminate evildoers, lewd musical girls [etc].
1508		Dunbar ‘Complainte to the King’ in Mackenzie Poems (1932) 40: Ane pykthank in a prelottis clais, With his wavill feit and wirrock tais.
1515–16		Skelton Magnyfycence line 1266: There be two lyther, rude and ranke, Symkyn Tytyvell and Pers Pykthanke.
c.1538		Thersytes (1550) D i: Prowde perts pykethancke, that pyked pernels purse.
c.1561		Awdeley Fraternitye of Vacabondes in Viles & Furnivall (1907) 14: This is a pickthanke knaue, that would make his Maister beleue that the Cowe is woode.
1576		U. Fulwell Art of Flattery 6th dialogue 27: Dialogue betweene Pierce Pikethank, Dronken Dickon, Dame Annat the alewife [...] Thou art an egregious flytterer, a deepe dissembler [...] a natural varlet, a knaue incarnate, and to conclude, a passing pikethanke, thou hast two faces vnder one hood lyke Janus.
1586		T. Newton Tryall of Mans Owne Self 135: Whether he haue giuen eare to anie pickethankes, and whispring talebearers .
1593		Passionate Morrice (1876) 80: I know some will say hee is a pick-thanke.
1600		Dekker Shoemakers’ Holiday I i: He sets more discord in a noble house, By one daies broching of his pickethanke tales.
1627		J. Taylor ‘An Armado’ in Works (1869) I 86: The Pickethanke, a Ship of great imployment that commonly sails out of sight or hearing.
1634		J. Withals Dictionarie in Eng. and Latine 314: A Pick-thank, or claw-back, Adulator.
1642		D. Rogers Naaman the Syrian 308: Many there bee who for praise, great vayles, to flatter and picke thanke with their Masters.
1653		Mercurius Democritus 5-12 Oct. 607: A brace of Pick-thanks, Make-bates or Tell-tales are to be broyled alive upon St Lawrences Gridyron.
1656		R. Fletcher (trans.) Martiall his Epigrams XI No. 67 106: Th’art both a Pick-thank, and a Detractor, A Cunning Cheater, and a Factor, A Lick-twat, and a Fencer too.
1669		R. L’Estrange Supplement of Fables (1692) CCCCIIIV 375: These Pick-thanks are enough to set Mankind together by the Ears; they live on Calumny and Slander.
1677		Otway Cheats of Scapin II i: The first thing shall be to cut the Throat of that perfidious Pick-thank Dog that has ruined me.
a.1682		Sir T. Browne Christian Morals I 20: Be deaf unto the suggestions of ... pick-thank or malevolent delators [F&H].
c.1698		B.E. Dict. Canting Crew n.p.: Pickthank a Tale-bearer, or an Insinuator by any means to curry Favour.
1705		N. Ward Honesty in Distress II 16: I’ll warr’nt the Baggage comes to pry about, And, like a Pickthank, find our Failings out.
1730		K. O’Hara Tom Thumb I ii: Out from my sight, base Pickthank, hie, begine!
1740		R. North Examen 278: He did it to pick-thank an Opportunity of getting more Money.
1781		Hicky’s Bengal Gaz. 9-16 June n.p.: Toad eaters, petty-foggers, and Pickthanks.
1789		J. O’Keeffe Highland Reel 56: Kick me, you little pick thank!
1796		Grose Classical Dict. of the Vulgar Tongue n.p.: Pickthank, a tale-bearer or mischief maker.
1811		Lex. Balatronicum [as cit. 1796].
1817		W. Scott Rob Roy (1883) 138: It is hard that persons of birth and rank and estate should be subjected to the official impertinence of such a paltry pickthank.
1822		R. Nares Gloss. (1888) II 656: pick-thanks. A flatterer, a person who is studious to gain favour, or to pick occasions for obtaining thanks. A word so common once, that it may be said to have been a favourite.
1914		Truth (Melbourne) 10 Jan. 11/7: Tufthunters, toadies, pickthanks, lickplatters, cringelings, snobs, and the James Chawles yellowplushes of the ‘servants’ ’alls’.