Freckle
late Middle English: alteration of dialect frecken, from Old Norse freknur (plural).
wiktionary
From Middle English freken, frekel, from Old Norse freknurpl (compare Swedish fräknar, Danish fregner), s-less variant of Old English sprecel from Proto-Germanic *sprekalą(“freckle”) (compare dialectal Norwegian sprekla, Middle High German spreckel), from Proto-Indo-European *sp(h)er(e)g-(“to strew, sprinkle”). Cognate with Albanian fruth(“measles”). More at spark. Related to spry, sprack.
etymonline
freckle (n.)
late 14c., also frecken, probably from Old Norse freknur (plural) "freckles" (source also of Icelandic frekna, Danish fregne, Swedish frägne "freckle"), from PIE *(s)preg- (2) "to jerk, scatter" (see sprout (v.)). Related: Freckles.
freckle (v.)
"to cover with spots," 1610s, from freckle (n.). Related: Freckled (from late 14c. as "spotted"); freckling.
