Milky

wiktionary

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From Middle English mylky, melky, equivalent to milk +‎ -y. Cognate with German milchig(“milky”), Swedish mjölkig(“milky”). Doublet of milchig.

etymonline

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milky (adj.)

late 14c., "milk-like in color or consistency," from milk (n.) + -y (2). Related: Milkily; milkiness.