displacer

[dis-pley-ser] /dɪsˈpleɪ sər/
noun
1.
a person or thing that displaces.
2.
plum (def 10).
Origin
1580-90; displace + -er1
Examples from the web for displacer
  • The displacer motion is affected by a gas spring action between the power piston and the displacer rod.
  • displacer and piston have reached bottom dead center together.