Synonyms for Submissive (same or very similar meaning)
WordNet sense 1 (abjectly submissive; characteristic of a slave or servant):
slavish, subservientWordNet sense 2 (submissive or fawning in attitude or behavior):
servileWordNet sense 3 (evidencing little spirit or courage; overly submissive or compliant):
meekWordNet sense 4 (showing humiliation or submissiveness):
abjectFrom the ODE community, based on WordNetadd/edit