Both nevlich and dufftich are adjectives (description words) that mean foggy.
Foggy adj = nevlich (when speaking about the weather)
Foggy adj = dufftich (as in fogged up; glasses, windows, etc)
💡 What’s the Difference?
nevlich
Use nevlich (foggy) when you’re talking about the weather—when it’s foggy outside and hard to see.
’Sis gans nevlich dimeiya.
’Sis am reiyra draus un nevlich dimeiya.
dufftich
On the other hand, use dufftich (foggy) when talking about an object that is fogged up; usually from steam or a difference in temperature—such as glass, windows, mirror, or eyeglasses.
Dufftich can also be used jokingly:
Mei brain is dufftich dimeiya.