conc▪ Unlike ↗¹muʕǧam ‘incomprehensible, unintelligible, obscure (language, speech)’ which is related to the complex of *‘dumbness’ (↗ʕǦM_3), ²muʕǧam is a PP from the vb. ↗ʔaʕǧama ‘to provide (a letter) with a diacriticaI point (with diacritical points)’ which in turn is a *Š-stem from ↗ʕaǧama ‘(to bite on s.th., e.g., a coin, a stone, etc.) to test its quality’, prob. denom. from ↗¹ʕaǧam ‘stone, kernel, pit, pip, seed (of fruit)’. The original meaning of the underlying vb. IV ʔaʕǧama is thus *‘to put stones, seeds, etc. on s.th. to make it discernable, to give s.th. a profile’.
▪ In ClassAr dictionaries (as reproduced in Lane), the meaning of the term ḥurūf al-muʕǧam is given as ‘the letters of the alphabet (of the language of the Arabs), most of which are distinguished by being dotted from the letters of other peoples’. This explanation combines ‘diacritical dotting’ with ‘other (non-Arab) peoples’ (↗²ʕaǧam) and thus suggests an etymological relation between the two, which, however, seems doubtful. Alternatively, the term is interpreted as short for »ḥurūf al-ḫaṭṭ al-muʕǧam ‘the letters of the dotted character’; or by al-muʕǧam is meant al-ʔiʕǧām [vn.], so that the meaning of ḥurūf al-muʕǧam is ‘[the letters] of which a property is the being dotted’«. The latter two explanations are prob. closer to the etymological truth.
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