(noun)
broadly, a long, loose-fitting, and often flowing outer garment worn over one's clothes, usually during a ceremony or formal occasion, typically as a symbol of one's profession, rank, or status (often used as "robes");
e.g. The judge was dressed in robes during the court session.
(verb)
to dress someone (or oneself) in a long and loose-fitting garment, especially for a ceremony or formal occasion;
e.g. The maids helped the queen robe for the ceremony.
(verb)
broadly, to dress someone or oneself, i.e. to put clothes on someone/oneself;
e.g. I wanted to robe myself in a magnificent dress for the party.