This multifunctional word has a couple of useful meanings. First, in a physical sense, it describes the condition of having the apex of an object — such as a pyramid or a cone — cut off and replaced by a plane section, usually parallel to the object’s base. Similarly, the word describes how something, whether tangible or intangible, is cut short or curtailed. It’s this latter definition that we’re using for the example sentence.
Example: Sally was relieved that the developer had truncated the day’s marathon project meeting because she and her team were under tight deadline pressure on a set of construction documents for another client.