IPA: /ɪˈnɛstɪməbl/
KK: /ɪˈnɛstəˌməbəl/
Something that cannot be measured or calculated because it is too valuable or important.
The support of my family during tough times has been inestimable.
Inestimable → It is formed from "in-" (meaning not) and "estimare" (meaning to estimate or value). The word "inestimable" means something that cannot be estimated or valued, indicating its immeasurable worth.
Think of something that is 'not' ('in-') able to be 'valued' ('estimare') — that's why inestimable refers to something of immeasurable worth.