The Semispatha and the Saex

[Renatus]

In the De Gladiis part of his Etymologiae Isidor writes: "Semispatium gladium est a media spatae longitudine appallatum [..]"

There are some highly questionable etymologies in Isidore. Do we really believe that gladius is so-named "because it divides the throat" (quod gulam dividit)? It is quite likely that Isidore simply took what seemed to him to be the obvious derivation and assumed that semispathium meant 'half a spatha'. Actually, as your quotation shows, the words he uses are semispatium and spatae, although he uses spatha in the preceeding paragraph. His etymology for spatha also seems pretty dubious; he believes that it comes from the Greek pathein, 'to suffer'.