The word волосы only exists now in plural form. Was the obsolete form волос ever used to refer to anything but a single strand of hair, like in a mass noun (e.g., мокрый волос instead of мокрые волосы)?
2 Answers
The word волосы only exists now in plural form.
I think "волосы" is a plural form of "волос", which is perfectly useful in its singular form. Apart from Wiktionary, I haven't found any other online dictionary where "волосы" is considered an independent word in and of itself. That could be because Wiktionary isn't limited to one page per word, they may have separate pages for each word form.
Was the obsolete form волос ever used to refer to anything but a single strand of hair, like in a mass noun (e.g., мокрый волос instead of мокрые волосы)?
Well, it isn't obsolete. The singular form is certainly used to refer to a single hair, as in тоньше волоса thinner than a hair.
And you're right — the singular form "волос" can be used as a mass noun. But keep in mind that such usage outside of set phrases (like конский волос horsehair) is rare and stylistically marked:
Бегемот только горько развёл руками и надел кепку на круглую голову, поросшую густым волосом, очень похожим на кошачью шерсть.
Булгаков, Мастер и Маргарита.
In other words, "мокрый волос" is not an error, but it would sound really odd in everyday conversation.
People may not use "во́лос" (mass noun) very often in speech nowadays, but it is used in fiction and poetry.
Глаза большие, чёрные, волос русый, воротничок белый под самое горлышко. [И. Грекова. Перелом (1987)]
Как ко̀ндор про̀летѐл, как во̀лос по̀редѐл, [С. Е. Вольф. «Неглубока вода под досочкой косой...» (1980-2000)]
Тучнѐют поля̀. Овѐчек стригу̀т ― осыпа̀ется во̀лос. Цветы̀ на землѐ, ждет пѐсни земля̀, И во̀т уже слы̀шится го̀рлицы го̀лос.
[С. И. Липкин. Спокойный приют : «Полуночный пляж. Немного пловцов...» (1991
Женский волос долог, зато ум короток, не зря так народ толкует. [С. И. Шуляк. Квартира номер девять. Роман с чертовщиной // «Волга», 2013] [
постоянно покупаем волос.