spam account

Etymology
It is possible that the term originally referred to a secondary email address which was created to be indiscriminately shared on the Internet and was hence expected to receive more spam than one's primary email address. The term was then applied to secondary social media accounts.

Another possible origin is that the term derives from the high volume of posts typical of this type of account.

Noun

 * 1) A personal social media (chiefly Instagram) account separate from one's public or main account, where one generally posts more raw, personal content, compared to the main account which features more polished, curated posts.