Walking on air is an idiom that is used to describe a feeling of extreme joy and elation. The crossword solutions for this term are JOYOUS (6 letters), ELATED (6 letters), HAPPY (5 letters), ECSTATIC (8 letters), DELIRIOUS (9 letters), orgasmic (8 letters), and cloudnine (9 letters). All of these words refer to a state of intense happiness and bliss, suggesting that the person is so overjoyed that they feel as if they are literally walking on air.