IPA: //sʌsˈtɛnʃən//
KK: /sʌsˈtɛnʃən/
The act of supporting or maintaining something, especially in terms of life or growth.
The sustentation of the ecosystem is crucial for the survival of many species.
Sustentation → It is formed from "sustinere" (from Latin, meaning to hold up or support) which combines "sub-" (meaning under) and "tenere" (meaning to hold). The word refers to the act of supporting or maintaining something.
Think of 'holding up' ('sustinere') something from 'under' ('sub-') — that's why sustentation means the act of support or maintenance.