system vs theology

system and theology both are nouns.

Word	Noun	Adjective	Verb	Adverb
system	Yes	No	No	No
theology	Yes	No	No	No

As nouns, theology is a hyponym of system; that is, theology is a word with a more specific, narrower meaning than system:

system (noun)	theology (noun)
instrumentality that combines interrelated interacting artifacts designed to work as a coherent entity	the learned profession acquired by specialized courses in religion (usually taught at a college or seminary)
an ordered manner; orderliness by virtue of being methodical and well organized	a particular system or school of religious beliefs and teachings
a group of physiologically or anatomically related organs or parts	the rational and systematic study of religion and its influences and of the nature of religious truth
the living body considered as made up of interdependent components forming a unified whole
a complex of methods or rules governing behavior
a procedure or process for obtaining an objective
an organized structure for arranging or classifying
a group of independent but interrelated elements comprising a unified whole
(physical chemistry) a sample of matter in which substances in different phases are in equilibrium