Urban Dictionary OOTNnighttime outfit heart symbolism is a term used to depict an outfit that is put on in the evening or for special occasions. symbolizes love, emotion, and affection. Therefore, an ootn showcases an fashionable and captivating attire that mirrors one's love for clothing and embraces the nighttime vibe. Sporting an ootn can elevate your confidence, make a statement, and exude elegance and charisma. Regardless of it's a glamorous dress or an chic suit, the ootn will ensure that you stand out and leave a lasting impression at any night event.