Subject
As a noun:<BR><B>1.</B> A branch of learning that forms a course of study.
In medical school, one of the subjects traditionally studied in the first year is anatomy.<BR><B>2.</B> A matter that is studied or otherwise considered.
Death is a subject often avoided by doctors in talking with patients.<BR><B>3.</B> The object of observation,, treatment, or research.
There are guidelines for the conduct of research involving human subjects at NIH.
<BR> The American Psychological Association (APA) has recommended replacing the term 'subject' by 'participant' to imply that the person consents to the research.
And if someone such as a baby cannot consent, the APA recommended the term 'individual.'