-Latry means "worship".
There are three parts to this root:
-later: worshiper (or worshipper)
-latrous: worshiping (or worshipping)
Some examples of this root include:
Heliolatry: helio + latry = worship of the sun
Idolater: picture, icon + later = worshipper of pictures or icons
Theolatrous: theo + latrous = woshipping a god
Any other derivatives?