compact
(1)紧密的，紧凑的
(2)坚实的
(3)小型的

• round guide
• rounding error
• rounding of corner
• rounding off
• roundness
• round-segment fused bifocal construction
• round-segment multifocal
• round-trip gain
• round-trip transit time
• round waveguide
• Rousseau diagram
• route surveying
• routine suitability
• routine test
• rovibronic transition
• row
• Rowland arrangement reflection grating
• Rowland circle
• Rowland-circle concave grating
• Rowland ghost
• Rowland grating
• Rowland mounting
• row matrix
• rubber
• rubber spring