work study vs time and motion study

work study and time and motion study both are nouns.

Word	Noun	Adjective	Verb	Adverb
work study	Yes	No	No	No
time and motion study	Yes	No	No	No

As nouns, work study and time and motion study are synonyms defined as:

work study and time and motion study: an analysis of a specific job in an effort to find the most efficient method in terms of time and effort

Other synonyms of work study include motion study, time-and-motion study, time-motion study, time study.

work study (noun)	time and motion study (noun)
an analysis of a specific job in an effort to find the most efficient method in terms of time and effort	an analysis of a specific job in an effort to find the most efficient method in terms of time and effort