From Wiktionary, the free dictionary
By surface analysis, ехтя́ (ehtjá, “to resound”) + -еж (-ež).
ехте́ж • (ehtéž) m
- echo, rumble
- “ехтеж”, in Речник на българския език [Dictionary of the Bulgarian Language] (in Bulgarian), Sofia: Bulgarian Academy of Sciences, 2014
- “ехтеж”, in Речник на българския език [Dictionary of the Bulgarian Language] (in Bulgarian), Chitanka, 2010