Engl. breath, German Atem, and Greek átmus
Are Atem and átmus “vapor, steam,” the latter known to us from atmosphere, related? Most probably, they are not, even though t in German Atem goes back to th (þ) and though the original vowel in Atem was also long. The vowel á in átmus is the product of a contracted diphthong (ae), with the digamma (F) in the middle. Indeed, some dictionaries hedge and say that perhaps the words are related after all or add that they have the same type of word formation.
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