1) Change 2) Make into soap 
to convert into soap
• (v. t.) To convert into soap, as tallow or any fat; hence (Chem.), to subject to any similar process, as that which ethereal salts undergo in decomposition; as, to saponify ethyl acetate.
Sa·pon'i·fy transitive verb [ imperfect & past participle Saponified ; present participle & verbal noun Saponifying .] [ Latin sapo , -onis , soap + -fy : confer French saponifier .] To convert into soap, a...
Type: Term Pronunciation: să-pon′i-fī Definitions: 1. To perform or undergo saponification.
[v] - chemistry: become converted into soap by being hydrolized into an acid and alcohol as a result of being treated with an alkali 2. [v] - chemistry: convert into soap by hydrolizing an ester into an acid and alcohol as a result of treating it with an alkali
saponify, saponifiable To be converted into soap or to convert a fat into soap, especially by reaction with an alkali.