semiotics vs semiology

semiotics and semiology both are nouns.

Word	Noun	Adjective	Verb	Adverb
semiotics	Yes	No	No	No
semiology	Yes	No	No	No

As nouns, semiotics and semiology are synonyms defined as:

semiotics and semiology: (philosophy) a philosophical theory of the functions of signs and symbols

semiotics (noun)	semiology (noun)
(philosophy) a philosophical theory of the functions of signs and symbols	(philosophy) a philosophical theory of the functions of signs and symbols