If "tack" refers to a small nail:
* Gwoździk (small nail, pin)
* Szpilka (pin, tack)
* Szpilka do tapicerki (upholstery tack)
If "tack" refers to a small piece of cloth used for sewing:
* Kawałek tkaniny (a piece of cloth)
* Szmatka (rag, small piece of cloth)
If "tack" refers to a direction or course:
* Kurs (course, direction)
* Kierunek (direction)
* Sposób (method, approach)
If "tack" refers to a style or technique:
* Styl (style)
* Technika (technique)
* Sposób (method, approach)
To provide the most accurate translation, please provide more context or the sentence where "tack" is used.