word 7 : activate
1. to make active; cause to function or act.
2. (physics) to render more reactive; excite.
3. (chemistry) to hasten reactions by various means.
4. to organize or create.
5. to convert into active derivatives.
6. to aerate (sewage) in order to accelerate decomposition of impure (organic) matter (by microorganisms).
see also : urban catalyst