shivah vs shibah

shivah and shibah both are nouns.

Word	Noun	Adjective	Verb	Adverb
shivah	Yes	No	No	No
shibah	Yes	No	No	No

As nouns, shivah and shibah are synonyms defined as:

shivah and shibah: (Judaism) a period of seven days of mourning after the death of close relative

Other synonyms of shivah include shiva.

shivah (noun)	shibah (noun)
(Judaism) a period of seven days of mourning after the death of close relative	(Judaism) a period of seven days of mourning after the death of close relative