Withdrawal symptoms vary with the substance, but some symptoms may include increased heart rate, shaking, insomnia, fatigue, and irritability. Substance abuse is continued use of a substance in spite of school-or work-related or interpersonal problems, but the user has not gotten dependent on the substance.The individual who abuses a substance may experience legal problems and may have problems fulfilling responsibilities, such as caring for a child.ithdrawal symptoms vary with the substance, but some symptoms may include increased heart rate, shaking, insomnia, fatigue, and irritability. Substance abuse is continued use of a substance in spite of school-or work-related or interpersonal problems, but the user has not gotten dependent on the substance.
ton. n. 1. A unit of weight equal to 2,000 pounds (0.907 metric ton or 907.18 kilograms). Also called net ton, short ton. 2. A unit of weight equal to 2,240 pounds (1.016 metric tons or 1,016.05 kilograms). Also called long ton. 3. A metric ton.
1 Ton. 2  Tonne, also known as a metric ton (t), equal to 1,000 kg (2,204.6226218 lb) or 1 megagram. 3  Tonnage, volume measurement used in maritime shipping, originally based on 100 cubic feet (2.8316846592 m 3).