Here are some words that start with "ny" and are 5 letters long:
- Nyala: a spiral-horned antelope native to the Horn of Africa and South Africa
- Nycto: relating to or occurring at night
- Nyala: a small, spiral-horned antelope of southern Africa
- Nyxis: a genus of moths of the family Erebidae.
- Nyala: a spiral-horned antelope native to the Horn of Africa and South Africa
- Nycto: relating to or occurring at night
It's worth noting that words that start with "ny" and are 5 letters long are rare, therefore the list provided is not exhaustive.