back (body part) surface 5 realizations
ACCEPTED Realization 1
Type Semantic evolution
Language Akkadian
Lexeme ṣēru
Meaning 1 back (body part)
Direction
Meaning 2 surface
Reference CAD: ṣ 138 Lane: 1653
Comment

The question is whether it was a “geographical” semantic shift from lexeme with a meaning 'back (body part)’ to a meaning -> ‘surface of the (earth)', or it was a syncretism of two independent lexemes with contamination of their meanings (via metaphorical reinterpretation): anatomical term for 'back' and 'back of the Earth'.

Cf. dictonaries (CAD, AHw.) consider it the same word as ṣēru ‘hinterland, open country, steppe', which is rather to be compared to Arb. ṣaḥrā صَحْرَاء 'desert area, desert' (> Sahara) (BK 1 1314).  

Meanwhile, cf. Ugr. ṯ̦r with the meaning 'back' and Arb. ḏ̣ahr- 'hinder part; back' (SED I no. 284).

ACCEPTED Realization 2
Type Polysemy
Language Classical Arabic
Lexeme ḏ̦ahr-
Meaning 1 back
Direction
Meaning 2 the upper side, surface ḏ̦ahr-u l-lisān-i
the upper surface of the tongue
Reference Lane: 1927-1928
Comment
ACCEPTED Realization 3
Type Polysemy
Language Latin
Lexeme dorsum
Meaning 1 back
Direction
Meaning 2 surface dorsum viae, dorsum maris
road surface, sea surface
Reference
Comment
NEW Realization 4
Type Polysemy
Language Somali
Lexeme dul(-sha)
Meaning 1 surface
Direction
Meaning 2 back (of an animal)
Reference Alejnikov 2012
Comment
ACCEPTED Realization 5
Type Polysemy
Language Ugaritic
Lexeme ṯ̦r
Meaning 1 back (body part)
Direction
Meaning 2 surface
Reference SED I: no. 284
Comment