yarn bomb
verb /ˈjɑːn bɒm/
  /ˈjɑːrn bɑːm/
(also yarn storm 
 /ˈjɑːn stɔːm/
  /ˈjɑːrn stɔːrm/
)Verb Forms
| present simple I / you / we / they yarn bomb |    /ˈjɑːn bɒm/   /ˈjɑːrn bɑːm/  | 
| he / she / it yarn bombs |    /ˈjɑːn bɒmz/   /ˈjɑːrn bɑːmz/  | 
| past simple yarn bombed |    /ˈjɑːn bɒmd/   /ˈjɑːrn bɑːmd/  | 
| past participle yarn bombed |    /ˈjɑːn bɒmd/   /ˈjɑːrn bɑːmd/  | 
| -ing form yarn bombing |    /ˈjɑːn bɒmɪŋ/   /ˈjɑːrn bɑːmɪŋ/  | 
Verb Forms
| present simple I / you / we / they yarn storm |    /ˈjɑːn stɔːm/   /ˈjɑːrn stɔːrm/  | 
| he / she / it yarn storms |    /ˈjɑːn stɔːmz/   /ˈjɑːrn stɔːrmz/  | 
| past simple yarn stormed |    /ˈjɑːn stɔːmd/   /ˈjɑːrn stɔːrmd/  | 
| past participle yarn stormed |    /ˈjɑːn stɔːmd/   /ˈjɑːrn stɔːrmd/  | 
| -ing form yarn storming |    /ˈjɑːn stɔːmɪŋ/   /ˈjɑːrn stɔːrmɪŋ/  | 
- yarn bomb something to decorate items in the streets with colourful pieces of knitting or other items made using wool, cotton, etc., often doing it secretly