簇がる[muragaru] to swarm
上簇[jouzoku] spinning of cocoons
簇生[zokusei] (of plants) growing in clusters
簇出[zokushutsu] springing up in clusters

太簇[taizoku] (in China) 3rd note of the ancient chromatic scale (approx. E)
簇出[soushutsu] springing up (in clusters)
簇々[zokuzoku] gathering

緩衝[kanshou] buffered
緩衝器[kanshouki] shock absorber
緩衝地帯[kanshouchitai] buffer zone
刺衝[shishou] stabbing
衝撃[shougeki] shock

衝撃波[shougekiha] shock wave
衝動[shoudou] impulse
衝動行為[shoudoukoui] shock action
衝動買い[shoudougai] impulsive buying
衝突[shoutotsu] collision