sweet alyssum vs sweet alison

sweet alyssum and sweet alison both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet alyssum	Yes	No	No	No
sweet alison	Yes	No	No	No

As nouns, sweet alyssum and sweet alison are synonyms defined as:

sweet alyssum and sweet alison: perennial European plant having clusters of small fragrant usually white flowers; widely grown in gardens

Other synonyms of sweet alyssum include Lobularia maritima.

sweet alyssum (noun)	sweet alison (noun)
perennial European plant having clusters of small fragrant usually white flowers; widely grown in gardens	perennial European plant having clusters of small fragrant usually white flowers; widely grown in gardens