ETYM Latin transactio, from transigere, transactum, to drive through, carry through, accomplish, transact; trans across, over + agere to drive; cf. French transaction. Related to Act, Agent.
The act of transacting within or between groups (as carrying on commercial activities); SYN. dealing, dealings.

A sequence of SQL statements whose effect is not accessible to other transactions until all the statements are executed.
A discrete activity within a computer system, such as an entry of a customer order or an update of an inventory item. Transactions are usually associated with database management, order entry, and other online systems.