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the celtics of Glasgow Glasgow Celtic Football Club Otherwise known as Celtic pronounced seltic not, as above, The Celtics. that is Boston
People pronounce it in two different ways, either with a hard C, like Keltic, or with a soft C like Seltic. Both ways are common.
There is no difference. The word is properly spelled "Celtic." Sometimes people pronounce it as if spelled "seltic" and sometimes as if spelled "keltic" but it is the same word, refering to anything related to the ancient people called "The Celts."
The word Celtic can be pronounced in two different ways, either as, Keltic or Seltic.
When referring to the Celtic people, their languages and culture, modern scholars tend to pronounce the word with a K-sound, recalling the original form of the word, which the Greek pronounced "Keltoi").When referring to sports teams that call themselves Celtics or Celts (bearing in mind that sports figures do not generally represent the most careful speakers), we use the S-sound.The Irish say Keltic and Kelts. Americans say Seltics and Selts. Both are technically correct. It just depends on whether you want to pronounce it the American way or the Irish way.There was at one point, and maybe still is, some preference depending on your region. Either can be said without being wrong, however:Celtic goes back through the French Celtique where the s-sound was acquired, coming from the Latin Celticus prior to that (where it was pronounced with a k). seltic would be the correct pronunciation currently, in keeping with modern English. There is authority for saying keltic from its origins, but no reason to do so anymore.Another Opinion:If it's the basketball team, it's "seltics".Otherwise, it sounds like "Keltiks"."Seltic" for the Scottish soccer club, "Keltic" for all things to do with the Keltoi, or as we call them today, the Celts.Though a lot of people in the US say "sel-tic", the correct way is "kel-tic." Reputable American and British dictionaries list both pronunciations but show one as preferred. Neither is unquestionably correct. The current trend in American dictionaries is away from maintaining the prior alignment with other American ce-- words (like century and ceramic) to the British influenced Keltic, which aligns with British use of Keramic for pottery. For thoughts on why we won't end up saying Keramic mugs, see the discussion item.