A → Wolf-Rayet star whose spectrum
is dominated by emission lines of ionized carbon: C III 5696 Å,
C III / C IV 4650 Å, C IV 5801-12 Å.
This type is divided in sub-types WC4 to WC9.
For theoretical models, a Wolf-Rayet star whose carbon abundance at surface is larger than
nitrogen abundance and has the abundance ratio (C + O) / He < 1 (in number).