baseborn

1. Ignoble; contemptible.
2. 1. Born of unwed parents; illegitimate.
   2. Of humble birth.

adjective

1. Born to parents who are not married to each other: bastard, illegitimate, misbegotten, natural, spurious, unlawful. See kin, law.
2. Lacking high station or birth: common, déclassé, declassed, humble, ignoble, lowly, mean, plebeian, unwashed, vulgar. Archaic base. See over/under.

The adjective has 2 meanings:

Meaning #1: of low birth or station (`base' is archaic in this sense)
  Synonyms: base, humble, lowly

Meaning #2: (archaic) illegitimate
  Synonym: base