Wali

Smooth, thin, as poi; fine, mashed, soft, powdery, supple, limber, as a dancer's body.

When you find that perfect poi, just the right consistency, it nice wali.  When you put hoʻo- in front of wali that becomes the action of making something smooth and thin.  Hoʻowali is the word used when mixing something like poi or dough, because your main goal when doing this is to get to that smooth, fine consistency.  NEVER a good thing to have lumpy poi.  You MUST hoʻowali until it is wali.  Bad karma to have lumpy poi.

Ua wali ka poi - The poi is smooth.
ʻuala hoʻowali ʻia - mashed sweet potatoes.

Nā mea hoʻowali o loko - digestive organs (literally "the smoothing things inside")