What is the meaning of the word "tact"?

Definitions:

Consideration in dealing with others and avoiding giving offense. NOUN
- The teacher showed tact by addressing the student's poor performance privately.
Refers to the sensitivity and skill in dealing with others, especially in delicate or difficult situations without causing offense. NOUN
- It takes tact to give honest feedback without hurting feelings.
The ability to deal with embarrassing situations carefully and without doing or saying anything that will annoy or upset other people. NOUN
- The host demonstrated tact by seating the guests thoughtfully to avoid any potential conflicts.
The ability to say or do the right thing in a diplomatic, considerate, or socially sensitive way. NOUN
- He lacked the tact needed to manage the tense discussion.