Arabic dual nouns (-eyn)

Farsi frequently borrows Arabic vocabulary, especially in legal and formal contexts. One notable borrowing is the Arabic dual suffix ـین, which indicates exactly two of something.

Farsi has adopted several of these as fixed everyday words for natural or logical pairs, such as والدین (parents), طرفین (both parties/sides), and زوجین (the couple/spouses).

Plural Agreement

Because Farsi grammar does not have a native dual form, it strictly treats Arabic dual nouns as standard plurals. When a dual noun is the subject, the verb must take a plural conjugation (like the suffix ـند).

Here is the rule in action in family court, where a couple might seek a consensual divorce (طلاق توافقی):

Notice how the dual subject pairs with the plural verb می‌خواهند. The same plural agreement applies when discussing parents and custody (حضانت):

Legal Disputes and Settlements

These dual nouns are extremely common when describing conflicts, negotiations, and court appearances. Whether the opposing sides are reaching a settlement (مصالحه) or engaging in a dispute (مجادله), the syntactic rule remains the same: the verb is always plural.