IPA: /ˈvɔɪdə/
KK: /ˈvɔɪdər/
A person or thing that empties or cancels something.
The voider of the contract ensured that all obligations were nullified.
Voider → It is formed from "void" (from Old French *voider*, meaning to empty) and "-er" (meaning a person who). A voider is a person who empties or removes something.
Think of someone who 'empties' ('void') something — the '-er' just means a person. A voider is someone who removes or empties.