нирец

From Proto-Slavic *nyra (“crack”) + -ец (-ec). Akin to Russian ны́ра (nýra, “dent, track”).

• IPA^(key):

ни́рец • (nírec) m

1. (dialectal) crack, crevice, dent (in a rock, cliff, cave, stone wall)

   Synonyms: про́цеп (prócep), пукнатина́ (puknatiná), ду́пка (dúpka), зъ́бел (zǎ́bel)

2. (by extension) small fault, fissure (on the ground)

   Synonyms: разло́м (razlóm), пазина́ (paziná)

• ни́рище (nírište) (augmentative)
• поно́р (ponór, “swallow hole”)

• “нирец”, in Речник на българския език [Dictionary of the Bulgarian Language] (in Bulgarian), Sofia: Bulgarian Academy of Sciences, 2014
• Nayden Gerov (1899) “ныре́ць”, in Рѣчникъ на Блъгарскꙑй язꙑкъ. Съ тлъкувание рѣчи-тꙑ на Блъгарскꙑ и на Русскꙑ. [Dictionary of the Bulgarian language]‎ (in Bulgarian), volume 3, Plovdiv: Дружествена печꙗтница "Съгласие.", page 285

Bulgarian Wikipedia has an article on:

Нирци

Wikipedia ^bg

From Proto-Slavic *nyrьcь, *nyrikъ, *nyrъkъ (“diver”). Cognate with Russian ныре́ц (nyréc, “diver”), ныро́к (nyrók, “diving duck, pochard”), Ukrainian нуре́ць (nurécʹ), пронуро́к (pronurók, “dipper (bird)”), Polish nurzyk (“guillemot”).

• IPA^(key):

нире́ц • (niréc) m (feminine ни́рка)

1. (literally) diver, dabber

   Synonyms: гмуре́ц (gmuréc), пота́пник (potápnik)

2. goosander, merganser, sawbill (diving sea duck of genus Mergus)

• голя́м нире́ц (goljám niréc, “great merganser, Mergus merganser”)
• сре́ден нире́ц (sréden niréc, “middle merganser, Mergus serrator”)
• ма́лък нире́ц (málǎk niréc, “small merganser, Mergus cucullatus”) (also called америка́нски нире́ц (amerikánski niréc))

• костену́рка (kostenúrka, “turtle”) (literally: bone-shelled diver)

• гмуре́ц (gmuréc, “grebe”) (neoavian diving bird, similar to goosanders)
• гмурка́ч (gmurkáč, “loob”) (neoavian diving bird, similar to goosanders)