soubriquet vs sobriquet

soubriquet and sobriquet both are nouns.

Word	Noun	Adjective	Verb	Adverb
soubriquet	Yes	No	No	No
sobriquet	Yes	No	No	No

As nouns, soubriquet and sobriquet are synonyms defined as:

soubriquet and sobriquet: a familiar name for a person (often a shortened version of a person's given name)

Other synonyms of soubriquet include byname, cognomen, moniker, nickname.

soubriquet (noun)	sobriquet (noun)
a familiar name for a person (often a shortened version of a person's given name)	a familiar name for a person (often a shortened version of a person's given name)