Scottish

wiktionary

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From Middle English Scottisch, Scotissch, Scotisch, scottissh, from Old English Scottysċ, Scyttisċ, equivalent to Scot +‎ -ish. Compare West Frisian Skotsk(“Scottish”), Dutch Schots(“Scottish”), German schottisch(“Scottish”), Danish skotsk(“Scottish”), Icelandic skoskur(“Scottish”). Doublet of Scotch.

etymonline

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Scottish (adj.)

late Old English Scottisc; see Scot + -ish. Related: Scottishness.