One of the synonyms for porcupines can be hedgehogs, which are small, spiky animals that are found in various parts of the world. Other possible synonyms could be quills or spines, which refer to the sharp, pointed projections that cover the bodies of porcupines and other similar creatures. Another term that might be used as a synonym for porcupines is echidnas, which are found in Australia and New Guinea and are known for their spiky quills and ability to roll up into a ball for protection. Overall, there are many different words that could be used as synonyms for porcupines, and each term might be more appropriate depending on the context in which it is being used.