By Anatoly Liberman at OUP: The Hebrew word “hostages” can be translated into English as “children of surety,” and in many languages the word for “hostage” means both “security, pledge” and “people captured (held) in pledge.” The Greek for “hostage” (hómēros) will come as a surprise to many. Is this, we wonder, the meaning of Homer’s name? Why was the most famous Greek in history called this? Since nothing is known about Homer, we will avoid guesswork. In any case, the word does not go back to the poet’s name: the opposite is true. Moreover, this noun occurs in neither the Iliad nor the Odyssey. Though its etymology is far from clear, hómēros does not seem to have emerged from any root meaning “pledge” or “security.” May the poet sleep in peace, while those whose only connection with Homer is by way of Homer Simpson enjoy their hero’s deeds. Needless to say, Homer is a fully acceptable name in today’s English-speaking world.
Contrary to Greek hómēros, many other European words for “hostage” make sense even to a non-specialist. Such is Italian statico (a little-known synonym for ostaggio), Russian zalozhnik (stress on the second syllable; zalog “pledge”; that is, “pledge-ling”), and even Latin obses, evidently, from ob-sed-s, though the connection between –ses and sedere “to sit” was probably no longer felt by Latin speakers (English obsess is not too far off!). Wherever we look, hostage means “pledge, security” and only then, by extension, “a person held as security.” In Ancient Greece and Rome, hostages were often handed over for the carrying out of an agreement and not as captives, and in medieval Europe, hostages were usually given, not taken.
Among the European words for “hostage,” the ones from Germanic are particularly obscure. In Old English, we find gīs(e)l ~ gȳsel (read ī as Modern English ee and ȳ as long German ü). The other Germanic languages had close cognates of gīsl but unlike Modern English, have retained them. Such are, for example, German Geisel and Dutch gijzel. Gisela, the wife of the Francian Viking king Rollo (from Hrólfr?), spoke a dialect of Romance but had a Germanic name that must have meant “pledge” (medieval marriages were certainly not made in heaven). To this day, we meet not only Homers but also Giselas. In Scandinavia, many men were called Gísli. The Saga of Gisli (Gísla saga) is one of the most memorable and intriguing tales that have come down to us from the Middle Ages.
Old Norse gísl is an obvious cognate of the words cited above. It continued into all the Modern Scandinavian languages, but strangely, some reconstructed protoform like geisla does not resemble any other Germanic word. Yet it seems to have strong ties with Celtic. Irish giall ~ geill “deposit, pledge” (from Old Irish gíall) looks similar to gīsel, and most language historians treat the Germanic word as a borrowing from Celtic. They reconstruct some ancient root like gheis- ~ ghis-, followed by a suffix.
Why this root meant “pledge” remains unknown: no light on it falls from Sanskrit, Greek, or Latin. The verb for “give” sounds a bit similar, but the similarity must probably have been due to chance. By contrast, the fact of borrowing need not surprise us. The ancient speakers of Celtic and Germanic lived in close proximity from time immemorial, and in some respects, the culture of the Celts was superior to that of their neighbors. Quite a few terms of industry and societal organization reached the ancestors of the Scandinavians, Germans, and Anglo-Saxons from the Celts. Hostage “pledge, security; a person taken as security” was, quite obviously, a legal term, part of the vocabulary of societal organization.
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