Proto-MSA

*ˁamḳ- - middle (Kogan 2015: 549)

M. Bittner (1909:14, 1915b:8) and W. Leslau are undoubtedly correct to derive it from PS *ˁmḳ ‘to be deep’ (CDG 63), notwithstanding a somewhat peculiar semantic development

PS
*ˁmḳ - to be deep (CDG 63)
Semantically unambiguous cognates to this root are missing from both Akkadian and MSA. Cf. Akk. emēḳu ‘to be wise’ and MSA *ˁamḳ- ‘midst, interior’.

Mehri
ˀāmḳ - middle (ML 24)
Jibbali
ˁamḳ - middle (JL 13)
Soqotri

ˁamḳ di- ‘in the middle of (spatial)’:

éʸhork mésen ouzhéten ˁaf ˁamḳ di-ḥaḷf ˁógiľ ḥe ˁag di-yetɛbíľin ʸhéˀerho érhon ‘I was going after some of my goats. Midway along, I met a man who was also gathering up his goats’ (CSOL II 12:16).

ˁamḳ di- ‘in the middle of (temporal)’:

kɔn šin níbit di-tímhɛr wa-nebóten ˁaf ˁamḳ di-šɔm ľísoʰ mέsɛ ‘It was the season of palm pollination in our land. We were pollinating (our trees), but in the middle of the day it rained’ (CSOL II 30:38)

wa-déroʰ ˁággi ˁaf ˁamḳ di-waḳt ṣáme ŝíbɛb ‘The father and the son lived together, and after a while the old man died’ (CSOL II 4:4).

be-ˁamḳ di- ‘in the middle of (spatial)’:

ˁamérho ḳarére tebánšar ˁin siyáraʰ be-ˁamḳ di-ˀórem wa-ˀal-ˀáraḥ tan maṭár ‘Our car may get a puncture tomorrow in the middle of the way and will not bring us to the airport’ (Naumkin et al. 2013b:545).

be-ˁamḳ di- ‘in the middle of (temporal)’:

tɛbíľoʰ ˁážeʰ díˀseʰ bíššoḷ be-ˁamḳ di-ḥteʰ be-téked ‘The woman gathered her things in the middle of the night, in a hurry’ (CSOL II 25:3).