When it comes to describing the size of something, there are a myriad of words that can be used in place of "turkey-sized". For instance, "gigantic" or "colossal" can be used to describe something that is particularly large. "Massive" or "immense" work well too. If you want to give the impression of something being smaller than turkey-sized, words like "petite" or "miniature" may be more appropriate. "Tiny" and "diminutive" also work well. Finally, you could also opt for comparative synonyms such as "larger than a breadbox" or "smaller than an ant". With so many synonyms at your disposal, it's easy to find the perfect word to describe the size of any object you encounter.