a person whose duties as an agent are delegated to him or her by another agent
2.
a person who works for or under the supervision of an agent
Word origin
[1810–20, Amer.; sub- + agent]This word is first recorded in the period 1810–20. Other words that entered Englishat around the same time include: duplex, dynamic, liberalism, nihilism, voodoosub- is a prefix occurring originally in loanwords from Latin (subject; subtract; subvert; subsidy). On this model, sub- is freely attached to elements of any origin and used with the meaning “under,” “below,”“beneath” (subalpine; substratum), “slightly,” “imperfectly,” “nearly” (subcolumnar; subtropical), “secondary,” “subordinate” (subcommittee; subplot)