concertina
noun [ C ] uk/ˌkɒn.səˈtiː.nə/ us/ˌkɑːn.sɚˈtiː.nə/
六角手风琴
a musical instrument with a folding middle part that is played by pushing both ends together with the hands and pressing buttons
concertina
verb [ I or T ] UK uk/ˌkɒn.səˈtiː.nə/ us/ˌkɑːn.sɚˈtiː.nə/
折叠；挤压；压叠在一起
to fold, crush, or push together
In the accident, several cars concertinaed into each other. 事故中，几辆车撞成一团。
figurative Could we concertina the three meetings into one morning? 我们能把3个会议压缩在一个上午开吗？