A combination of two words is called تركيب. For منع صرف, the relevant form is a fused compound proper name, such as حَضْرَمَوْتُ or مَعْدِيْكَرِبُ. The two original words now identify one person or place.
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The Governing Rule
Cause of Ghayr Munsarif: Compound Proper Names
A combination of two words is called تركيب. For منع صرف, the relevant form is a fused compound proper name, such as حَضْرَمَوْتُ or مَعْدِيْكَرِبُ. The two original words now identify one person or place.