Green’s Dictionary of Slang

tack n.5

[tacky adj.1 ]

(orig. US) bad taste.

[UK]Video Today Apr. 33/4: Any interest in this sordid tack lies in the role it plays in Cohen’s regression since the days of The Terminator [OED].
[UK]Guardian 18 Aug. 🌐 But not all tack is created equal – 80s tack may have been big this summer but stick with it in autumn and you’ll just be plain tacky rather than tacky chic. To stay ahead, check out Kate Moss with her peroxide crop, or the shift towards bleached denim. Yes, the look of the season is Essex tack, much to everyone’s secret delight. At last you can break out your shoulderpads again or go for stilettos with jeans.

In compounds

tack attack (n.)

(orig. US) a rush of bad taste or an experience of bad taste.

Probert Encyc. 🌐 Tack attack is British slang for a bout of bad taste.
Time Out Toronto 228: Tack attack As if to offset the spectacular natural beauty of the area, the City of Niagara Falls is, let’s face it. pretty tacky.