Q: Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.
So basically, I know the name for both sides of a coin, yet not the coin itself. In other words, when you refer to a coin, you don't want to say 'this object with one side heads, and the other tails', you would want to say 'this coin'. What I want is a general term to refer to two ideas, that are the absolute opposite to each other. I can't really use the word 'concept', or 'idea', because such words are already assigned to the very concepts/ideas themselves.
A:
polar opposites: polar opposite (plural polar opposites): The complete opposite, opposite in every way. 'Polar opposites' might also refer to the scientific or technical definition of two things having exactly opposing or inverted polarity, sign, orientation, or some other property.