This is the 541st most frequent Greek word.
προπονητή
Coach.
Here, "προπονητής" refers to a person who trains and manages a sports team.
Ο προπονητής της ομάδας είναι αυστηρός, αλλά δίκαιος.
The team's coach is strict but fair.
In this sentence, "προπονητής" is used to mean a trainer or instructor in a non-sports context, such as a workshop or seminar.
Αύριο ξεκινάμε με έναν νέο προπονητή για το σεμινάριο.
Tomorrow we begin with a new trainer for the seminar.
Here, "προπονητής" is referenced conceptually as the role of someone who provides guidance and motivation in general.