Simple Definition:
Polarity refers to the property of having two opposite or contrasting aspects or conditions. It is the quality of something that can be divided into two parts that are completely different from each other. For example, a battery has positive (+) and negative (-) poles. One pole is positively charged, and the other is negatively charged.
Very Simple Definition:
Polarity means having two completely different parts.
For example, a magnet has a north and a south pole, and each of them produces a different type of field [invisible force that pushes or pulls].