cal·pain 
(kălpān′)
(kălpān′)n.
A proteolytic enzyme regulated by the concentration of calcium ions.
[Probably CAL(CIUM) + P(ROTE)A(SE) + -IN.]
- partial tone
- partible
- participance
- participant
- participate
- participation
- participational
- participative
- participator
- participatory
- participial
- participially
- participle
- particle
- particle accelerator
- particle beam
- particleboard
- particle board
- particle decay
- particle physics
- parti-colored
- particular
- particularism
- particularist
- particularistic