вечер vs вчера
Is вечер (evening) related to вчера (yesterday)? The words sound so similar, I feel like they have to be related in proto-Slavic or something! Does anyone have any information on this? Thanks in advance.
You're right. Вьчера is an old form of the instrumental case of the word вечер in Old Russian. Here ь (ерь) is extra-short or reduced и. After so named "падения редуцированных" ("the fall (vanishing) of extra-short vowels" - actually I don't know how to say it in English) it transformed into вчера. You can read more about it on https://lexicography.online/etymology/в/вчера
Интересно. Возможно корни отсюда? https://ru.chabad.org/library/article_cdo/aid/1681082