411 REFERENCE · Wiktionary
H II region
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
Alternative forms
en HII region HII region H-II region
Etymology
From a being region of space having mul HII HII emission lines in its spectrum.
Noun
mul H II region
en astronomy A large nebula of gas and plasma of glowing low density in which star formation has recently taken place.
Related terms
en HII emission line, HII emission line, H-II emission line
en HI region, HI region, H-I region, H I region
en terms containing Roman numerals