periodyl[化] 12-羟-9,10-二碘油酸periodn.一段时间；周期；时期；课时；学时；句号；月经periodontal atrophy牙周萎缩periodparallelogram周期平行四边形period of gestation[法] 妊娠期, 怀孕期间periodontal splints牙周夹period of expansion发展期period of retention固位期period of guarantee[经] 保证期限, 担保期period of vibration振荡周期,振动周期periodontal abscess牙周脓肿,根周脓肿periodontal varnish[医] 牙周护剂