snap on/off phrasal verbphr v SWITCH ON OR OFFto switch something on or off, or to switch on or off  开/关〔某物〕 A light snapped on in one of the huts. 其中有一间小屋的灯亮了。
 snap something ↔ on/off Kathy snapped off the light. 凯西把灯关掉。
  snap on/off• The light trained on his bed snaps off.• The satellite and more than 12 miles of tether linking it to Columbia snapped on Feb. 25.• His tormentors had snapped off the lights as they wished him goodnight, and it was completely dark.
 →  snap on/off  at snap1(4)