-ē- is irregular instead of the expected -ā-. Note that both dictionaries consider it the same word as ṣēru 'hinterland, open country, steppe' [ibid.], which is rather to compare to ARB ṣaḥārā 'champ dépourvue de végétation, plaine vaste et déserte; Sahara' [BK 1 1314]. See also eṣem/nṣēru 'backbone, spine' OB, SB, NA [CAD e 343], [AHw 251], a composed word < *eṣmu 'bone' (see *ʕat_̣m-(at-), No. ) plus ṣēru 'back'
угаритский:ẓr 'Rücken' [Aist 272] (note the absence of h)
In [CAD ṣ 261], the AMARNA word is also quoted as zu-uh_-ru-ma, translated '(on my) back' implying -ma is an adverb marker
арабский:d_̣ahr- 'dos' [BK 2 145-146]
тиграй (тигринья):č̣ǝra 'coda' [Bas 931]
амхарский:č̣ǝra 'hair at the end of an animal's tail' [K 2211]
гафат:č̣ǝra 'queue' [LGaf 194]
харари:č̣ǝra 'tail'
восточноэфиопские:Sel č̣ǝra, Wol č̣ǝrä 'tail'
гураге:all č̣ǝra 'tail'; MUH č̣ǝrǝyä 'hump of an animal' [LGur 190].
Hard to separate from CHA MUH MSQ č̣ǝyä, EŽA č̣ǝyyä, ENN GYE čǝyä, END čiyä 'hump of a cow' [ibid. 192]. Leslau hesitates to chose between the explanation by an augmented r and by a loss of r (the latter being much more natural than the former). The proto-form *č̣irǝyä <*t_̣i(h)r-?
NOTES:Eth. *č̣ǝra 'tail' is regarded by Leslau as a Cushitism. Note the preposition with a derived meaning 'back' > 'on, over' (used with or without other prepositions) to be reconstructed as PSEM: AKK ṣēru 'over, upon, above, etc.' (above); UGR b-ẓr 'darauf' (adv.), l-ẓr 'auf, nach, von' (prep.) [Aist 272]; SAB b-ẓhr 'at the back of' [SD 171]; MSA: MHR d_̣ār 'on' [LM 86] (under d_̣yr), HRS d_̣ār 'on, over' [JH 29] (strangely under d_̣ʕr), JIB d_̣ér 'on, over' [JJ 50] (under d_̣(y)r), SOQ ṭhar 'sur' [LS 200]. Absence of *-h- is an interesting parallel between continental MSA languages and UGR, probably due to the word's high frequency as a preposition; -h- in SOQ may either be "parasite" or reflect the etymological *-h-.
It is not clear whether this root is related or homonymous to the term 'midday, afternoon' usually interpreted as 'back (summit) of the day', cf. CAN: MOAB ʕd hṣhrm 'until the afternoon' [HJ 964], HBR ṣohŏrayim 'noon' [KB 1008]; ARM: JUD ṭihărā 'midday' [Ja 530], SYR ṭahrā 'meridies' [Brock 269]; ARB ẓuhr- 'heure de midi' [BK 2 145-6]; MSA: MHR d_̣ahr 'noon, midday' [JM 83], HRS d_̣ahr 'noon' [JH 29], JIB d_̣óhur 'noon, midday' [JJ 48], SOQ ḍuhr and d_̣uhr 'midi' [LS 361] (d_̣ohr 'noon', according to [JHrs 29]).
Cf. HBR ṣōhar 'roof' [KB 1008], with a possible meaning shift from 'back'.
MOD ETH *č̣ira(y) 'tail; hump' is to be compared with certain reservations as *č̣ may reflect several SEM "emphatics"; this comparison would rather imply metathesis: *č̣ira(y) <*t_̣irah <*t_̣ihar.
It is hard to say whether TGR ṣǝrärit 'muscle, tender flesh of the muscle' [LH 636-7], ṣǝrwät 'muscle' [ibid. 637] and AMH č̣ora 'nerve in the flesh' [K 2211] are related to the present root with a meaning shift.
Note GEZ and other ETH ṣora 'to bear, carry, etc.' [LGz 567]; Leslau quotes Rundgren who connects this word with ARB ẓahr- 'back', ṣora in this case originally meaning 'to carry on the back'. This verb, however, is rather to compare to SOQ ṣwr 'porter' [LS 347], which makes improbable its linking to *t_̣Vhr- (SOQ ṣ < *ṣ and not < *t_̣).
An isolated MSA example, HRS d_̣ahr 'camel's back, back' [JH 29], is almost certainly an Arabism, while MSA *ẓ̂ahr '(camel's) back', for lack of coherent explanation of *ẓ̂ (SEM *ṣ̂ {} *ĉ̣) has to be treated as a variant root: MHR ẑāhǝr 'back of a camel, strong back' [JM 475],̣ HRS źahr 'back' [JH 151], JIB ẓ̂ɛhǝr 'back' [ibid. 324].