Synonyms for Subject (same or very similar meaning)
WordNet sense 1 (a person who is subjected to experimental or other observational procedures; someone who is an object of investigation):
case, case, guinea pig
WordNet sense 2 (a person who owes allegiance to that nation):
national
WordNet sense 3 (the subject matter of a conversation or discussion):
theme, topic
WordNet sense 4 (a branch of knowledge):
bailiwick, discipline, field, study, branch of knowledge, field of study, subject area, subject field
WordNet sense 5 (some situation or event that is thought about):
issue, matter
WordNet sense 6 (something (a person or object or scene) selected by an artist or photographer for graphic representation):
content, content, depicted object
WordNet sense 7 ((of goods or funds) subject to taxation):
nonexempt, taxable
WordNet sense 8 (make subservient; force to submit or subdue):
subjugate
WordNet sense 9 (possibly accepting or permitting):
capable, open
WordNet sense 10 ((often followed by `of' or `to') yielding readily to or capable of):
susceptible
WordNet sense 11 (being under the power or sovereignty of another or others):
dependent
WordNet sense 12 (subject or submissive to authority or the control of another):
subordinate
WordNet sense 13 (refer for judgment or consideration):
submit
WordNet sense 14 (acted upon; influenced):
affected
From the ODE community, based on WordNet
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