scalp (n.) Look up scalp at Dictionary.com
mid-14c., "top of the head (including hair)," presumably from a Scandinavian source (though exact cognates are wanting) related to Old Norse skalli "a bald head," skalpr "sheath, scabbard,"from the source of scale (n.1). French scalpe, German, Danish, Swedish skalp are from English. Meaning "head skin and hair as proof of death or a victory trophy" is from c.1600.
scalp (v.) Look up scalp at Dictionary.com
"to cut off (someone's) scalp," 1670s, from scalp (n.), originally in reference to North American Indians. For ticket re-selling sense, see scalper. Related: Scalped; scalping. Compare German skalpern, Danish skalpere, Swedish skalpera. French scalper is from Germanic. Similarity to Latin scalpere "to cut, carve" is accidental.