whatchamacallit

英 [ˈwɒtʃəməkɔːlɪt]

美 [ˈwɑːtʃəməkɔːlɪt]

n.  (想不起名称时说)叫什么来着

牛津词典

noun

• （想不起名称时说）叫什么来着
  used when you cannot think of the name of sth
  1. Have you got a whatchamacallit? You know… a screwdriver?
     你有一把…叫什么来着的？你知道的…螺丝刀吗？

英英释义

noun

• something unspecified whose name is either forgotten or not known
  1. she eased the ball-shaped doodad back into its socket
  2. there may be some great new gizmo around the corner that you will want to use
  Synonym:doodaddoohickeydoojiggergimmickgizmogismogubbinsthingamabobthingumabobthingmabobthingamajigthingumajigthingmajigthingummywhatchamacallumwhatsiswidget