Some noises can be scary. Nile crocodiles definitely are scary.
Nile crocodiles, noises, needles, northern rubber boa and narcotics are scary things that begin with the letter N.
Jeepers
Need is another word for require and begins with an N.
N- 5 letters:nannynasalnavelnoiseneedynylonnorthniecenastynoosenannyninthniftynoblenovelnaivenakednastynativenethernervenevernichenexusninnyninjanightnotchnudgenurse
nugget
Another name for abnormal swelling starting with 'N' is a Nodule.
nuholictan
norm
noticed
Noodles
nestling
newt
needless