DECO originally came from the word "art deco" which refers to a decorative style that was popular in the 1920s and 1930s. Synonyms for this word could include things like ornamentation, embellishment, adornment, or decoration. Other words that could be used to describe this type of style might include things like art nouveau, modernist, or even retro. Depending on the context in which the word is being used, it might be appropriate to look for words that suggest a particular era or time period, or to focus on more general terms that evoke a sense of elegance or sophistication.