-latry

The ending '-latry', found in 'idolatry' and a number of other words such as 'iconolatry' and 'Mariolatry', comes from the Greek λατρεία (latreia), which originally meant the state or condition of a hired labourer but came to mean divine worship or the service which human beings owe to the gods. The word λατρεία is used in this latter sense in the dialogues of the Greek philosopher Plato, in the Septuagint (i.e., the Greek translation of the Old Testament), and in the Greek New Testament.

Although the Greek word λατρεία when used to mean 'worship' was not used in a derogatory sense, its English descendant '-latry' always implies criticism or disapproval: it has the meaning of improper or excessive worship or veneration. Thus idolatry is the [improper] worship of idols, iconolatry is the [excessive] veneration of icons or religious images, and Mariolatry is the [excessive] veneration of the Virgin Mary, the mother of Jesus - a term largely used by Protestants, who tend not to single Mary out for special honour, about Roman Catholics, who do.

The adjective from 'idolatry' is 'idolatrous' while a person who worships idols is an idolater (if male) and an idolatress (if female). The nouns 'iconolatry' and 'Mariolatry' produce analogous forms, viz., 'iconolatrous', 'iconolater', and 'iconolatress'; and 'Mariolatrous', 'Mariolater', and 'Mariolatress'.

The Greek λατρεία is also the origin of the rather obscure English word 'latria' (pronounced ler-TRY-er, IPA: /lə ˈtraɪ ə/). 'Latria' is a technical term in Roman Catholic theology and means 'the adoration that is properly offered only to God'.