Specifically refers to the crimson hakama traditionally worn by Shinto shrine maidens (miko) or noblewomen at the imperial court.
The shrine maiden wears a white kosode and a red hakama.
Court ladies in the Heian period wore red hakama.
Standard spelling with the possessive particle の.
Abbreviated spelling without の; less common but still used.
Compound of 紅 (くれない, 'crimson') + の (possessive particle) + 袴 (はかま, 'hakama'). The exact historical origin of the red color's significance is uncertain, but it is traditionally associated with shrine maidens and court attire.