Was it known before the discipline of linguistics came into being?
Also, is "stressed schwa" a self-contradiction?
Was it known before the discipline of linguistics came into being?
Also, is "stressed schwa" a self-contradiction?
Shwa” - literally "emptiness" - starts off as a technical term in Hebrew grammar as formulated in the Middle Ages. It designates the diacritic consisting of two vertical dots below a letter, indicating that that letter is not followed by any vowel. Its function is the same as the Arabic sukūn, on which it is evidently modelled. But in certain contexts the shwa is realised as a short vowel, to break up what would otherwise be an uncomfortable cluster of consonants. The European Hebraists at some point declared the latter to be a short central vowel, In the 19th century the Hebrew term was (mis)appropriated to designate such a vowel in all languages.
Also, is "stressed schwa" a self-contradiction?
No, regardless of what definition of schwa is used. If schwa means mid-central vowel then many languages have this in stressed syllables. If schwa means "reduced vowel" then a phonemic distinction between full and reduced vowels in stressed syllables is attested in the Khanty languages.