unsaponified fat.    From Wordnet, Princeton University. 

Soap, to be suitable for the purpose, must be free from uncombined caustic alkali, unsaponified fat, silicates, and rosin.    From Wordnik.com.  [The Handbook of Soap Manufacture] Reference

I didn't and ended up with unsaponified PKO lumps throughout my bars ... and since the PKO didn't saponify, the rest of the bar was lye heavy.    From Wordnik.com.  [FLOAP soap] Reference

Although it is possible, with care, to produce neutral soaps of good appearance and firm touch by this method, cold-process soaps are very liable to contain both free alkali and unsaponified fat, and have now fallen considerably into disrepute.    From Wordnik.com.  [The Handbook of Soap Manufacture] Reference

It was also further explained why the potash soaps generally sold to the public were unfit for general use, owing to their not being neutral -- that is to say, containing a considerable excess of free or unsaponified alkali, which acts injuriously on the fiber of any textile material, and causes sore hands if used for household or laundry purposes.    From Wordnik.com.  [Scientific American Supplement, No. 360, November 25, 1882] Reference

Theoretically, he considered a soap-stock made entirely from beef tallow the most suitable for the purpose, but in practice found that the best results were obtained by using a superfatted soap made from a blend of one part of olive oil with eight parts of beef tallow, saponified with a mixture of two parts of soda to one part of potash, sufficient fat being employed to leave an excess of 3 or 4 per cent. unsaponified.    From Wordnik.com.  [The Handbook of Soap Manufacture] Reference

Cholesterol in unsaponified matter, 120.    From Wordnik.com.  [The Handbook of Soap Manufacture] Reference