Toodeloo is a colloquial term used to express farewell or goodbye. It is likely that the term originated from the French phrase "à tout à l'heure," meaning "see you later". Although it's not a commonly used term anymore, there are various other expressions that mean the same thing. For instance, some popular alternatives include "bye-bye", "see ya", "so long", "cheerio" and "adios". These expressions are used to let people know that you are leaving or that the conversation is over. These synonyms have different tones, so choose the one that suits the situation or relationship with the person you are saying goodbye to. Regardless of which one you use, the sentiment and intention are the same, to wish someone well and say goodbye.