Dec is a common abbreviation for the month of December, however, it can also refer to the prefix meaning "ten". As a prefix, dec can be found in many words such as decade, decathlon, and decimal. Other synonyms for the word dec, in the sense of "ten", include deca and deci. Deca refers to a group of ten, while deci means a tenth of something. Outside of the prefix usage, there are no other direct synonyms for the abbreviation dec, as it refers specifically to the month of December. However, there are synonyms for December, such as Yuletide or the festive season, that can be used in place of the specific month.