America is the only English speaking country that pronounces Z as "zee"

In most dialects of English, the letter’s name is ‘zed’ /ˈzɛd/, reflecting its derivation from the Greek zeta, but in American English, its name is ‘zee’ /ˈziː/, deriving from a late 17th century English dialectal form.

Another English dialectal form is izzard /ˈɪzərd/. It dates from the mid-18th century and probably derives from Occitan izèda or the French ézed, whose reconstructed Latin form would be*idzēta, perhaps a popular form with a prosthetic vowel.

Other languages spell the letter’s name in a similar way: zeta in Italian, Spanish and Icelandic (no longer part of its alphabet but found in personal names), zäta in Swedish, zæt in Danish,zet in Dutch, Polish, Romanian and Czech, Zett in German (capitalised as noun), zett in Norwegian, zède in French, and zê in Portuguese.

Several languages lacking /z/ as phoneme render it as /ts/~/dz/, e.g. zeta /tsetɑ/ or /tset/ in Finnish. In Mandarin Chinese pinyin the name of the letter Z is pronounced [tsɨ], although the English ‘zed’ and American English ‘zee’ have become very common.

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