To cut the end off something and leave it shorter than it should be. The word carries a feeling of an interruption, not a tidy edit: a truncated speech, a truncated holiday, a truncated career all sound like something was stopped before it finished. That is why it is common in computing — a database column that only holds 20 letters will truncate a longer name, silently dropping whatever doesn't fit — and in reports about meetings, seasons, and lives cut short. It is a formal word; in everyday talk people say 'cut short'. It is very often used in the passive ('the message was truncated') or as an adjective ('a truncated version'). In science, 'truncate' can also describe a shape that ends flat where you would expect a point, like a leaf or a cone with its tip cut off.

截短、截斷（電腦領域常說「截斷」，如字串被截斷）