From the s-m-ʿ root, masmaʿ relates to hearing. In the textbook's three nominal slots:
Word / formMeaning / explanation
مَسْمَعٌsingular.
مَسْمَعَانِdual.
مَسَامِعُbroken plural.
Masāmiʿ is also attested in Arabic in contexts connected with hearing. The full lexical sense of a word depends on usage and context, not morphology alone.