The same marginal note gives another usage: if nadmān means nādim, “regretful,” its feminine, according to the book, is nadmā, not nadmāna.
In that sense nadmān is a diptote. The spelling is the same, but the meaning and feminine formation differ.
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Nadmān Meaning Regretful
Diptote Causes — Additional Alif and Nūn and Their Conditions
The same marginal note gives another usage: if nadmān means nādim, “regretful,” its feminine, according to the book, is nadmā, not nadmāna.
In that sense nadmān is a diptote. The spelling is the same, but the meaning and feminine formation differ.