1. An act that requires use of resources or time. In Program Evaluation and Review Technique (PERT), an activity is represented by an arrow on a PERT chart.
2. In
investing, the amount of a
security's relative
trading volume; that is, the amount of
money flowing into and out of a security in trading. A high amount of activity means that many
shares of the security are being bought and sold at a high rate, while a low level of activity indicates the opposite.