extemporaneous vs extemporary

extemporaneous and extemporary both are adjectives.

Word	Noun	Adjective	Verb	Adverb
extemporaneous	No	Yes	No	No
extemporary	No	Yes	No	No

As adjectives, extemporaneous and extemporary are synonyms defined as:

extemporaneous and extemporary: with little or no preparation or forethought

Other synonyms of extemporaneous include ad-lib, extempore, impromptu, off-the-cuff, offhand, offhanded, unrehearsed.

extemporaneous (adjective)	extemporary (adjective)
with little or no preparation or forethought	with little or no preparation or forethought