Definition from Wiktionary, the free dictionary
- Late; overdue or delayed.
- He yawned, then raised a tardy hand over his mouth.
- ineffectual; slow witted, slow to act, or dullard
- His tardy performance bordered on incompetence.
Usage notes 
- The term suggests habitual lateness.
- Somewhat dated.
later in relation to the proper time
ineffectual; slow witted, slow to act, or dullard
tardy (plural tardies)
- (US) A piece of paper given to students who are late to class.
- The teacher gave her a tardy because she did not come into the classroom until after the bell.