IPA: /ˌɒptɪmaɪˈzeɪʃən/
KK: /ɑːptɪmaɪˈzeɪʃən/
The process of making something as effective or functional as possible.
The optimisation of the software improved its performance significantly.
Optimisation → It is formed from "optimus" (meaning best) and "-isation" (a suffix used to form nouns indicating a process or action). The word "optimisation" refers to the process of making something as effective or functional as possible, or making it the best it can be.
Think of 'best' ('optimus') and remember that 'optimisation' means the process of making something the best it can be.