The word "nylgan" may seem difficult to spell at first, but it follows a fairly regular pattern in terms of its pronunciation. In IPA phonetic transcription, the word would be spelled /ˈnaɪlɡən/. The "ny" sound at the beginning is pronounced like the "ni" in "nitrogen", followed by a long "i" sound. The "l" sound is pronounced clearly and is followed by a hard "g". Finally, the word ends with an unstressed "a" sound, pronounced like the "a" in "sofa".
An animal of Northern India of the goat kind, as large as a stag.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.