上弦: first quarter wind up a cloc ...杆件: member上弦杆: top boom; top chord; upper boom; upper chord member; upper cord侧架上弦杆: side frame tochord驼背上弦杆: camel back top chord屋架上弦杆: principal rafter曲线形上弦杆: curved top chord上弦: 1.[天文学] first quarter (of the moon)2.(上钟表发条) wind up a clock or watch; principal rafter◇上弦月 the moon at the first quarter弦杆: boom bar; boom element; boom member; boom rod; chord member底弦杆: bottom chord副弦杆: subchrod拉弦杆: tension chord目上弦: margin of the upper eyelid; margin of upper eyelids上弦梁: tochord上弦月: first quarter; first-quarter moon; waxing moon上弦子: chord下弦杆: bottom boom bar; bottom chord bar; low-boom; lower boom; lower chord弦；弦杆: chord斜弦杆: inclined chord正弦杆: sine bar斜杆件: inclined member悬杆件: suspension rod〔表〕上弦，上发条。: stem-winding半月,上弦月: first quarter moon背弓上弦法: step-in method; step-through
