section
(1)部分，区域，段
(2)截面，断面，剖面
(3)拼件

• oxygen
• oxygen hydrogen torch
• oxygenization
• oxygen laser
• oxymeter
• oxyopia
• oylet
• oz
• ozone
• ozone cutoff
• ozone spectroscopy
• ozonosphere
• paassive resonant cavity
• pabry-perot mirror
• pabry-perot spectroscopy
• pace
• pacer
• pachymeter
• package sealing with laser
• packet
• packet of energy
• packing
• packing density
• packing efficiency
• packing fraction of fibre