1) Worship 
worship of one god without excluding belief in others
• (n.) Worship of a single deity.
(from the article `polytheism`) ...focus of worship. Within the framework of another part of the same ritual tradition, another god may be selected as supreme focus. Kathenotheism ... ...fashion as a term. It was introduced by the eminent 19th-century philologist and scholar in comparative mythology and religion Max Müller ... T...
Mo·nol'a·try noun [ Mono- + Greek ... worship.] Worship of a single deity. 
[n] - the worship of a single god but without claiming that it is the only god
monolatry The worship of one god, where other gods may supposedly exist.
noun the worship of a single god but without claiming that it is the only god
the worship of only one god although other gods are recognized as existing.