Learn Farsi: اشتقاق یک زیرمجموعه از صرف در زبان است. - Derivation is a subcategory of morphology in language.

The prefix zir- means 'under', 'sub-', or 'infra-'. The word majmu'e means 'collection', 'set', or 'group'. By attaching zir-, we get zir-majmu'e, meaning 'subset' or 'subcategory'. This is a very common way modern Farsi creates formal and scientific vocabulary.

I usually see sarf meaning 'spending' (like spending time or money). How does it mean 'morphology' here?

In the context of language and grammar, sarf translates to 'morphology' or 'inflection'. The Arabic root implies turning or changing a thing's form. This is why it applies to changing money or spending, but also to changing the shapes of words for conjugation or morphology. You will often hear traditional grammar referred to as sarf o nahv (morphology and syntax).

Why does the sentence use az (from) after zir-majmu'e instead of just connecting it with an ezafe?

In English, we say a subcategory 'of' something. However, in Farsi, when you are talking about subsets, parts, or fractions of a larger whole, you typically use az (from). The logic is that the subset is drawn from the larger category, so you say zir-majmu'e az sarf rather than connecting them with the ezafe vowel.

Is the word eshteqâq (derivation) related to other common vocabulary?

Yes, eshteqâq is an Arabic verbal noun meaning 'derivation'. You might already know its related adjective moshtaq, which means 'derived' and is also the mathematical term for 'derivative'. Recognizing these root patterns helps you unlock highly formal linguistic or scientific terms.