noun
secondary account; alt account; backup account
Internet slang for an extra social media or online service account, often used for privacy, testing, or separating identities. Compare with サブ垢.
See also: サブ垢
副アカで本名を出さずに投稿している。
I post from my alt account without revealing my real name.
副アカを作って、趣味の話だけをするようにした。
I made a secondary account and decided to only talk about my hobbies there.
Synonymous; サブ垢 is more common and uses サブ (sub) instead of 副. Both are internet slang.
Abbreviation of 副アカウント (fuku-akaunto, 'sub account'). アカ is a common clipping of アカウント in online slang. The ateji spelling 副垢 uses 垢 for its reading アカ.