Carnine is a relatively rare word, but there are several synonyms that can be used instead. One of the most common is carnation, which refers to a specific shade of pink color that is reminiscent of the flower of the same name. Another possible synonym is carmine, which is another shade of red that is often used in art and design. Other synonyms for carnine might include scarlet, crimson, or ruby, all of which are shades of red with slightly different tones and hues. Ultimately, the best synonym for carnine will depend on the specific context in which it is being used and the intended meaning of the word.