Riba
From Islamic law
Religious and customary lawContract and obligations
What it means
A term for gain from lending that Islamic law forbids. It is often translated as 'interest' or 'usury', and the translation is itself a subject of scholarly debate.
Why it travels badly
'Interest' and 'usury' are modern economic terms, while riba is a religious-law category defined in the Quran and in the classical sources. Scholars differ on exactly which forms of lending it covers, and modern Islamic finance is built on structures that avoid it.
How other systems say it
riba
Applied under Islamic law, with banking and finance regulated through structures that avoid riba.
riba / fawa'id
The civil code permits interest within limits, and Islamic finance operates beside conventional banking.
interest / usury
Interest is lawful; usury refers to excessive interest, defined by statute or case law.
Tip for translators and students
Do not translate riba as 'interest' without a note, since that decides a point scholars debate.
Related: Waqf, Good faith
Updated October 2026. Spotted a mistake? Tell us.
TheLawToKnow Tools’s glossary is an educational overview of the main differences between legal systems. It is not legal advice.
