mash·gi·ach or
mash·gi·ah 
(mäsh-g
ēä
)
n. pl. mash·gi·chim or
mash·gi·him (-g
ēĭm, -g
ē-
ēm
)
An Orthodox rabbi, or a person appointed or approved by such a rabbi, whose responsibility is to prevent violations of Jewish dietary laws by inspection of slaughterhouses, meat markets, and restaurants where food assumed to be kosher is prepared for the public.
[Hebrew mašgîaḥ, from hišgîaḥ, to look, inspect; see šgḥ in the Appendix of Semitic roots.]