Reconstructions

Proto-MSA
*rṭḥ - to chop (meat); to arrange properly (ML 331)
Proto-MSA
*sgd - to take away (LS 150)
Proto-MSA
*slb - to wait (Kogan 2015:569)
The origin of Proto-MSA *slb ‘to wait’ is unknown. (Kogan 2015:569)
Proto-MSA
*sar - behind (Kogan 2015:569)
The origin of Proto-MSA *sar ‘behind’ is uncertain. Contra W. Leslau and M. Bittner (1914:15), any connection with PS *ˀaṯar- ‘trace’ can be safely excluded for phonological reasons. Quite far-fetched is the comparison between the MSA terms and Arb. sarīr- ‘the part where the head rests upon the neck’ (Lane 1339), sarāt- ‘back’ (ibid. 1353), Amh. säräsär ‘vertebra, spinal cord’ (AED 487) suggested in SED I No. 253. Shall one rather compare Hbr. swr ‘to turn aside’ (HALOT 748), assuming a semantic development from the more original meaning “to turn back”? (Kogan 2015:569)
Proto-MSA
*šbḥ - to cross, spread legs (Kogan 2015:596)
Proto-MSA
*šaḫar- - old man (Kogan 2015:571)
The origin of Proto-MSA *šaḫar- ‘old man’ is uncertain. Any connection with Akk. šuḫarruru ‘to become dazed, still, numb with fear’ (CAD Š₃ 203), Syr. šḥar ‘timuit’ (LSyr. 771)? One wonders whether Arb. sḫr (II) ‘to constrain, to compel to what one does not desire, to bring into subjection’ (Lane 1324) may also be ultimately related. (Kogan 2015:571)
Proto-MSA
*šVkay- - sword (Kogan 2015:571)

The origin is unknown. Contra M. Bittner (1915b:28) and W. Leslau, hardly any connection with Arb. škk ‘to pierce with the spear’, since Arb. š does not regularly correspond to š in MSA. Note Tgr. sakyät ‘iron-chips that fall off when a sword is whetted; edge of a sword’. (Kogan 2015:571)

Proto-MSA
*šny - to seed, to cultivate (Kogan 2015:517)

The etymology of Proto-MSA *šny ‘to seed, to cultivate’ is uncertain. Har. säňi ‘seed’ (EDH 141), Sel. säňe, Wol. säňňe and Zwy. säňi ‘seed, crop’ (EDG 555) are in all probability borrowed from Cushitic (Oromo saňňi, Somali šuni), but the Cushitic terms, in their turn, may be related to the MSA ones as cognates, thus pointing to a fairly archaic Afroasiatic root completely lost elsewhere in Semitic if not compared to Akk. ašnan (Militarev 1999:394). (Kogan 2015:571)

Proto-MSA
*šṣ̂r - to be green (Kogan 2015:542)
“Proto-MSA *šṣ̂r ‘to be green’ comes close to Arb. ḫḍr with the same meaning (Lane 754), but the extremely problematic correspondence *š vs. *ḫ makes a straightforward acceptance of this equation rather unappealing (see further Bittner 1915b:67, Bulakh 2004:276‒277). There is no trace of PS *wrḳ ‘to be green’ in MSA.” (Kogan 2015:542)
Proto-MSA
*šVṭp-at- - tray for fodder (Kogan 2015:572)
The origin of Proto-MSA *šVṭp-at- ‘tray for fodder’ is unknown. (Kogan 2015:572)