1) Devitalise 2) Enervate 3) Sap 1) Devitalise 2) Make lifeless 3) Sap of life or energy 4) Weaken 
• (v. t.) To deprive of life or vitality.
(de-vi´tәl-īz) to deprive of vitality or of life.
De·vi'tal·ize transitive verb To deprive of life or vitality. -- 
To remove the nerve of a tooth or an organ.
Type: Term Pronunciation: dē-vī′tăl-īz Definitions: 1. To deprive of vitality or of vital properties.
[v] - sap of life or energy
devitalize, devitlise (British) 1. To deprive of vitality or of life or vital properties. 2. To make lifeless; to weaken. 3. To deprive something of its strength, vigor, or life.
devitalise verb sap of life or energy; `The recession devitalized the economy`
to deprive of vitality or vital properties; make lifeless; weaken.