corresponding point 對應點corrosion 腐蝕cosine law of illumination 照度餘弦定律cosmic dust 宇宙塵cosmic radiation 宇宙輻射cosmic rays 宇宙線cosmic velocity 宇宙速度cosmical constant 宇宙常數cosmical meteorology 宇宙氣象學cosmic-ray shower 宇宙線射叢cosmology 宇宙學Cosmos 宇宙衛星cosmos 宇宙co-spectrum 協譜cost function 成本函數cost-benefit analysis [成]本[效]益分析cost-effectiveness [成]本[效]益比cotidal hour 滿潮時距cotidal line 同潮[時]線cotton ball cloud 棉球雲cotton-belt climate 棉帶氣候Couette flow 庫以退流couloir de grain 颮溝Coulomb's law 庫倫定律count 計數counter 計數器；反counter r