Polluter/pəˈluːtər/ Definition 1 of 1Pro Tip 1/3Human Responsibility Often used to highlight human activities causing environmental harm. The city identified local factories as the primary polluters of the river. Pro Tip 2/3Negative Connotation Has a strong negative undertone, blames for contamination problems. During the debate, the senator referred to the company as a notorious polluter. Pro Tip 3/3Broad Usage Can refer to a range of sources, not only industrial, like cars or smokers. Cars are significant polluters due to their exhaust emissions.