The name of NEWCOMB is of ancient origin. Etymologists are not agreed as to the word's ultimate derivation. Some say it comes from the Anglo-Saxon NEWE, meaning "new", and COMB, meaning "a valley", which, if correct, indicates that NEWCOMB is a place name (one derived from a place of habitation).

Other writers, however, assert that the surname was originally NEWCOME or NEWCOMEN and that it meant "a stranger, a newcomer".

"In the United States the name is now almost invariably spelled NEWCOMB; whereas, in Canada, the more common form is NEWCOMBE. A few of the other variant spellings the name has adopted in the course of its long and honorable history are Newcom, Newcomen, Neucomen, Neucome, Newcome, Neucum, Neucom, Nucum, Nucumb, Neukomb, Newkomb, Neucombe, Neucomb, Newcum, and Newkombe.

According to extant records, the earliest ancestors of the family lived in Lincolnshire, England. Here, at Saltsfletby, a Hugh Newcomen or Newcome was flourishing during the reign of Richard Coeur de Lion (1189-1199). The present Saltfletby (or Saltfleetby) branch of the family is, therefore, over seven hundred years old.

Courtesy of:
GENEALOGICAL AND HISTORICAL SKETCH
from Roots Research Bureau, Ltd, NY
"The Name and Family of Newcomb."