e·mer·i·tus 
(ĭ-mĕrĭ-təs)
(ĭ-mĕrĭ-təs)adj.
Retired but retaining an honorary title corresponding to that held immediately before retirement: a professor emeritus.
n. pl. e·mer·i·ti (-tī′)
One who is retired but retains an honorary title corresponding to that held immediately before retirement.
[Latin ēmeritus, past participle of ēmerērī, to earn by service : ē-, ex-, from; see EX- + merērī, to deserve, earn; see (s)mer-2 in the Appendix of Indo-European roots.]