Expressions (phrases, clauses, etc.), Godan verb with 'mu' ending
to poke one's nose into another's affairs; to have a hand in; to take a (deep) interest in; to meddle in
彼女は何にでも首を突っ込みたがる。She is curious about anything. to poke one's head (into a room)
Also written 首をつっこむ【くびをつっこむ】、首を突っこむ【くびをつっこむ】