It is an expression to indicate that a Japanese sentence is read with wrong delimiters, such as 'Benkei ga naginata wo motte sashi koroshita' (Benkei stabbed... to death with a naginata) mistakenly read as 'Benkei ga na, ginata wo motte sa, shikoroshita.'
「弁慶が薙刀を持って刺し殺した」という文を「弁慶がな、ぎなたを持ってさ、し殺した」と区切りを間違えて読むこと。