- natatory
- natatory seta
- naupliar eye
- nauplius
- nectophore
- nectosac
- nectosome
- nekton
- nematocysts
- nepheloid layer
- neritic
- neuropodium
- neuston
- non-tentacular marginal bulb
- notch
- notochord
- notopodium
- nuchal cartilage
- nuchal epaulettes
- nuchal folds
- nuchal organ
- nuchal papilla
- nuchal region
- nuchal slits
- nucleus
- nurse