It is very common, particularly amongst Australians, to confuse Tack and Tact in the context of comparing two different courses:
Erroneous: He took a different tact to me instead of
Correct: He took a different tack to me.
|Usage||Tack refers to direction||Tact refers to avoiding giving offence|
Definition of Tact
tact : noun
1. a keen sense of what to say or do to avoid giving offense; skill in dealing with difficult or delicate situations.
2. a keen sense of what is appropriate, tasteful, or aesthetically pleasing; taste; discrimination.
Definition of Tack (in this context)
tack1 : noun
1. a course of action or conduct, especially one differing from some preceding or other course.
2. one of the movements of a zigzag course on land.