Proto-MSA
*ṭad - one
(Kogan 2015:543)
“Identical to Qat. ṭd ‘one’ (LIQ 77), but one may doubt that this completely isolated term is autochthonous in ESA (rather, an MSA substratum or adstratum influence has to be surmised). There is hardly any trace of PS *ˀaḥad- ‘one’ in MSA. Further background of *ṭad- is enigmatic. One may be tempted to follow M. Bittner who analyzes it as an amalgamation of *ˀaḥad- with some other element (but hardly the relative pronoun *ḏV- as Bittner assumes.” (Kogan 2015:543)