patio vs terrace

patio and terrace both are nouns.

Word	Noun	Adjective	Verb	Adverb
patio	Yes	No	No	No
terrace	Yes	No	Yes	No

As nouns, patio and terrace are synonyms defined as:

patio (noun)	terrace (noun)
usually paved outdoor area adjoining a residence	usually paved outdoor area adjoining a residence
	a row of houses built in a similar style and having common dividing walls (or the street on which they face)
	a level shelf of land interrupting a declivity (with steep slopes above and below)

patio (verb)	terrace (verb)
	make into terraces as for cultivation
	provide (a house) with a terrace