κραββατον is initially Macedonian word according to Hessychius!
The Greek krábbatos is a popular word, of late certificate and has no ethymology in the Greek language . The fact that one can find it at a sicilian poet (Rhinton,
IIIe S. av.n.è.) and that the phonetic correspondence with Latin grabatus is irregular resulted in thinking that, in the two languages, the word is a loan. It is the
track followed by Kretschmer.
It is supposes a word Illyrien or Macedonian (?) *grabu which would be a name of tree and of which it finds correspondents in various
- dialectical modern Greeks grábos (Épire) and gábros (Arcadie) which indicates species of oaks
- the ombrien Grabovius (Eugubines Tables) epithet divine not explained
The semantic evolution would pass then from the tree to wood, then with the object made of wood, an evolution known from other examples (Greek drus(δρύς) "oak"
> dóru (δόρυ) "lance"). The grabat or krabat would be thus a simple wood bed, probably without more practical
comfort but for brancarder sick or wounded lifted from the floor...
grábion 'torch' (PIE *grabh-, 'hornbeam', Umbrian Grabovius an oak-god, etymologically linked by LSJ and Pokorny to Attic κράβ(β)ατος kráb(b)atos
'couch, bed', Latin grabātus - which LSJ derives from Macedonian - hence modern Greek κρεβάτι kreváti 'bed')
"I know too, of many Attic writerswho
use idioms of the Macedonians as a result of intercourse with them.”( Athenaeus .. Deipnosophistae, III. 121-122)
It is also posible that out of this noun for bed, one has developed the verb "kreva" > to lift up.