IPA: /ˈriːdʒənt/
KK: /ˈriːdʒənt/
A person who governs or rules, especially in place of a monarch who is unable to rule due to being too young, absent, or disabled.
The regent made important decisions while the king was away.
Regent → It is formed from "regere" (meaning to rule) and the suffix "-ent" (indicating an agent or one who performs an action). A regent is one who rules or governs on behalf of another, especially in the absence of a monarch.
Think of someone who 'rules' ('regere') in place of another — that's what a regent does.