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fitness tracker - n. a wearable device or a computer application that records a person’s daily physical activity, together with other data relating to their fitness or health, such as the number of calories burned, heart rate, etc.
accurate - adj. able to produce results that are correct
calorie - n. a unit of heat used to indicate the amount of energy that foods will produce in the human body
stationary - adj. not moving : staying in one place or position
error - n. something that is not correct
profile - n. a brief written description that provides information about someone or something
