sou'-sou'-west vs south-southwest

sou'-sou'-west is a noun but south-southwest is not a noun.

Word	Noun	Adjective	Verb	Adverb
sou'-sou'-west	Yes	No	No	Yes
south-southwest	No	No	No	Yes

As adverbs, sou'-sou'-west and south-southwest are synonyms defined as:

sou'-sou'-west and south-southwest: to, toward, or in the south southwest

sou'-sou'-west (noun)	south-southwest (noun)
the compass point midway between south and southwest

sou'-sou'-west (adverb)	south-southwest (adverb)
to, toward, or in the south southwest	to, toward, or in the south southwest