IPA: //nɒnˈɪnkʌmbənt//
KK: /nɑnˈɪŋkʌmbənt/
A person who is not currently holding a particular position or office.
The nonincumbent candidate has a fresh perspective on the issues.
Nonincumbent → It is formed from "non-" (meaning not) and "incumbent" (from Latin "incumbere", meaning to lie upon or to rest). The word "nonincumbent" refers to someone who is not currently holding a position or office, thus not lying upon it.
Think of 'not' ('non-') being applied to someone who is 'lying upon' a position ('incumbent'). This helps you remember that a nonincumbent is someone who does not currently hold that position.