Missionary has several different usages. One of which is people who go out and try to convert people to their religion in any of a variety of ways. Certainly there are also other folks who also go under the title missionary, with other specialties.

Although I have wondered whether or not proselytizing via example is at all effective. Does being religious and behaving in an emulatable way serve as a means of inspiring conversion? If it does, then those teachers, engineers, and translators may be as capable evangelists as any overtly seductive preacher.