The term "obnoxious liquid" refers to any liquid that has an unpleasant odor or taste. There are various synonyms for this term, which include foul, offensive, repulsive, disgusting, noxious, revolting, vile, and nauseating. A liquid can be obnoxious due to several reasons, such as its chemical composition, decomposition, bacterial growth, or contamination. It can cause health hazards, discomfort, and irritation to people who come in contact with it. Therefore, it's essential to identify and address obnoxious liquids with appropriate measures such as disposal, treatment, or proper storage to prevent any adverse impacts.