de·cen·ni·um 
(dĭ-sĕnē-əm)
(dĭ-sĕnē-əm)n. pl. de·cen·ni·ums or de·cen·ni·a (-sĕnē-ə)
A period of ten years; a decade.
[Latin, from decennis, lasting for ten years : decem, ten; see dek in the Appendix of Indo-European roots + annus, year; see at- in the Appendix of Indo-European roots.]
- polycystic ovary syndrome
- polycythemia
- polydactyl
- polydactylism
- polydactyly
- polydentate
- polydipsia
- polydipsic
- polyelectrolyte
- polyembryonic
- polyembryony
- polyene
- polyester
- polyesterification
- polyestrous
- polyether
- polyethylene
- polyethylene glycol
- polygala
- polygamist
- polygamous
- polygamously
- polygamy
- polygene
- polygenesis