WordNet sense 1 (low or inferior in station or quality):

humble, low, modest, small

WordNet sense 2 (of or characteristic of low rank or importance):

inferior

WordNet sense 3 (used of unskilled work (especially domestic work)):

menial

WordNet sense 4 (not having or showing or requiring special skill or proficiency):

unskilled

WordNet sense 5 (inferior in rank or status):

petty, secondary, subaltern, subordinate, junior-grade, lower-ranking

WordNet sense 6 (younger; lower in rank; shorter in length of tenure or service):

junior

WordNet sense 7 (of low birth or station (`base' is archaic in this sense)):

base, baseborn

WordNet sense 8 (of humble birth or origins):

lowborn