Reference books lead D. E. Rosenthal, E. V. Dzhandzhakova, N. P. Kabanova. Handbook of spelling, pronunciation, literary editing such a rule of writing "e" and "e" in the root of borrowed words:
It seems that everything is unambiguous, but this is at first glance.
There are many exceptions to the rule, and the variants of each new loan fluctuate between "e" and "e". Even if a foreign word has long been mastered in Russian, its derivatives are not immune from incorrect spelling. Therefore, next to the realtor appear real estate services. Sometimes the error gets into books, for example, a comic about a superhero called "Batman: The Long Halloween ", although the name of the holiday in Russian follows Academic Spelling Dictionary / Reference and information portal "Literacy.
Why does the letter "e" appear where the sound [e] is clearly heard? It's about the history of the language.
The letter "e" is fixed I. V. Nechaeva. "Mayor", "peer", "sir" and the problem of using the letter "e" after consonants / Culture of writing in the alphabet much earlier than the opponent. In native Russian words, there was always a soft consonant before the sound [e], and the letter "e" began to denote this softness, as in the words forest and sister . At the same time, in borrowings before the XVIII century, "e" was written even after hard consonants. Then the originally soft "w", "w", "c" hardened, but the "e" remained in place, for example in words like six and chain. It turned out that they began to write it after both a hard and a soft consonant. So modern index and cottage became possible.
The letter "e" hit I. V. Nechaeva. "Mayor", "peer", "sir" and the problem of using the letter "e" after consonants / Culture of writing in the Russian alphabet in 1708, when the civil alphabet was adopted. It was used in borrowings after vowels, for example in the words poet and dieta. Like any innovation in the language, the letter "e" caused rejection .
In the "Russian Grammar" Mikhail Lomonosov wrote M. V. Lomonosov. Russian grammar : "It's not good... to invent new letters for foreign accents." Alexander Sumarokov spoke A. P. Sumarokov. The complete collection of all works in verse and prose even sharper: "The literature that is most repugnant to both me and G. Lomonosov is unworthy to talk about it." Both of them suggested to give up the extra letter and write "e" everywhere instead.
Despite Lomonosov's opinion, the letter "e" has gained a foothold in the language and even expanded its positions. In the XIX century, philologist Yakov Groth proposed Ya. K. Grot. Russian spelling use it in borrowings only at the beginning of a word and after vowels, and in other cases write "e". And he also introduced an exception — the word peer with the letter "e", so as not to confuse it with the Russian pen in sentences like "I don't have a pen". The scientist called it "avoiding doublethink."
Over time, there were more exceptions. These included the words mayor, sir, plein air and master (to distinguish from the measure of length meter). Later this list included rap and racket. And the more borrowings appeared in the Russian language, the more exceptions were fixed by dictionaries: fantasy, hatchback, sandwich, laptop.
As a result, each new foreign-language word with great difficulty develops a permanent normative spelling. Everything is so variable that even academic recommendations change. For example, the Rosenthal Handbook published in 1999 offered D. E. Rosenthal, E. V. Dzhandzhakova, N. P. Kabanova. Handbook of spelling, pronunciation, literary editing write zen Buddhism with "e", but in a newer spelling dictionary the first part of the same word is given Academic Spelling Dictionary / Reference and information portal "Literacy.
Now the general trend is to write borrowings with the letter "e" in order not to increase the number of exception words. Therefore cashback hit Academic Spelling Dictionary / Reference and information portal "Literacy.
In cases where doubts and difficulties arise, it is better to check the spelling of using the dictionary . The latest edition of the "Russian Spelling Dictionary" will do (so far this edition is Russian Russian Spelling Dictionary: about 200,000 words / V. V. Vinogradov Institute of the Russian Language of the Russian Academy of Sciences 2018) or the resource "Academos" of the V. V. Vinogradov Institute of the Russian Language of the Russian Academy of Sciences. Unlike the printed version, "Academos" is updated every year. For example, 151 new entries appeared in it in 2022. Among them are the words jetlag and pokerface — both with an "e".