its not "quite clear" by any means
Yam Suph - Wikipedia, the free encyclopedia
The appropriate translation of the phrase remains a matter of dispute, as does the exact location referred to.
More conjecturally, it has also been suggested that
suph may be related to the Hebrew
suphah ("storm") or
soph ("end"), referring to the events of the Reed/Red Sea escape itself:
The crossing of the sea signaled the end of the sojourn in Egypt and it certainly was the end of the Egyptian army that pursued the fleeing Hebrews (Ex 14:23-29; 15:4-5). After this event at yam suph, perhaps the verb soph, meaning "destroy" and "come to an end," originated (cf. Amos 3:15; Jer 8:13; Isa 66:17; Psa 73:19). Another possible development of this root is the word
suphah, meaning "storm-wind"...The meanings "end" and "storm-wind" would have constituted nice puns on the event that took place at the yam suph.
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