(名詞/不可數) 被留在公共場所作為裝飾品的針織或鉤織品 (knitted or crocheted items)。
A new generation of guerrilla knitters are sweeping Britain, "yarnbombing" lampposts, postboxes and fences. Those in Generation Z, roughly aged 15 to 24, are getting behind the trend, which is also known as kniffiti, where a person crochets or knits something and attaches it to public property. Young Britons are "doing kniffiti in a big way", according to Emma Leith, who runs knitting classes across the UK.
[thetimes.co.uk, 16 April 2022]