drum
(1)鼓，鼓形物
(2)磁鼓
(3)鼓轮
(4)滚筒
(5)绕线架

• screw testing interferometer
• screw thread
• screw thread gage
• screw thread micrometer
• screw-type lens mount
• scroll
• scuff-resistant coating
• Seal
• sealed nitrogen laser
• sealed-off counter
• sealing
• sealing screw
• sealing washer
• sealing wax
• seal leakage
• seal material
• seamless
• search
• search-track IR-radiometer
• seasoning
• second
• secondary
• secondary aberration
• secondary axis
• secondary battery