ineffectual vs otiose

ineffectual and otiose both are adjectives.

Word	Noun	Adjective	Verb	Adverb
ineffectual	No	Yes	No	No
otiose	No	Yes	No	No

As adjectives, ineffectual and otiose are synonyms defined as:

Other synonyms of ineffectual include futile, meaningless, unavailing.

ineffectual (adjective)	otiose (adjective)
not producing an intended effect	disinclined to work or exertion
lacking in power or forcefulness	producing no result or effect
producing no result or effect	serving no useful purpose; having no excuse for being