repay
v.v. to pay back money that you borrowed from someone. You can also use it to describe doing something kind for someone who helped you.
v. to pay back money owed to a person or entity; to return a favour or service in kind. Transitive — requires a direct object representing either the debt or the recipient.
I will repay the loan next month.
She promised to repay his kindness by helping him move into his new apartment this weekend.
The government struggled to repay its international creditors after the sudden economic downturn reduced tax revenues and depleted the national reserves.
From Old French repaier (“to pay back”), from re- + paiier (“to pay”), from Latin pācāre (“to settle, to make peaceful”), from pāx (“peace”) + -ō (forming verbs). Equivalent to re- + pay. Cognate with repacify and French repayer (“to pay again”).
The verb is transitive and takes a direct object; often used with 'for' when referring to the reason for the payment.
I will repay back the moneyI will repay the moneyThe prefix 're-' already means 'back', so adding the word 'back' is redundant.