A complete intransitive verb takes neither a complement nor an object.

Literal

Complete intransitive-verb [topic-は] complement [also-も] object [also-も] not-take.

完全自動詞 'complete intransitive verb,' 補語 'complement,' 目的語 'object' — technical grammar terminology. The ~も…も…ない pattern means 'neither X nor Y.' A dry textbook definition.