A tactical report was a type of report on a current military situation.
In 2266, during the Neutral Zone Incursion, the USS Enterprise broadcasted tactical reports to the nearest command base every quarter of an hour. The reports gave information on the position and status of the starship. (TOS: "Balance of Terror")
In 2375, Chakotay, while posing as Jason Hayek to infiltrate the training simulation on Terrasphere 8, used a tactical report due in the morning as an excuse to finish his date with "Valerie Archer". (VOY: "In the Flesh")
In 2376, Chakotay presented Seven of Nine with the latest tactical reports from Tuvok, but Seven was distracted by concerns about her ability to instruct the Borg children aboard the USS Voyager. (VOY: "Ashes to Ashes")