[neither fish nor fowl] also [neither fish, flesh, nor fowl] Something […]

[neither here nor there] {adj. phr.} Not important to the thing […]

[neither hide nor hair] See: [HIDE OR HAIR].

[neither rhyme nor reason] {n. phr.} No emotional or intellectual substance. […]

[Nellie] See: [NICE NELLY] or [NICE NELLIE], [NERVOUS NELLIE].

[Nelly] See: [NICE NELLY] or [NICE NELLIE], [NERVOUS NELLIE].

[nerve] See: [GET ON ONE'S NERVES], [GET UP THE NERVE].

[nervous breakdown] {n.} A mild or severe attack of mental illness; […]

[Nervous Nellie] {n.}, {informal} A timid person who lacks determination and […]

[nervous prostration] {n.} An illness of the mind that makes you […]