cov ‧ e ‧ nant /ˈkʌv ə nənt/ BrE AmE noun [countable]
[ Date: 1200-1300 ; Language: Old French ; Origin: covenir 'to agree' , from Latin convenire ; ⇨ ↑ convenient ]
a legal agreement in which someone promises to pay a person or organization an amount of money regularly ⇨ endowment
—covenant verb [intransitive and transitive] :
He covenanted to pay £30 a month into the fund.