17-letter words containing f, a, n, v
- ventilation shaft — a shaft in a mine, tunnel, or building used for providing ventilation or fresh air
- vibrofluidization — Vibrofluidization is when vibration is used to make particles move in a fluidized bed.
- zone of avoidance — the area of the sky in the plane of the Milky Way where interstellar dust obscures visible light so that no distant galaxies can be observed.