用法:
1 part of a mechanism that moves up and down 柱塞; 活塞.

用法:
2 (in plumbing) rubber cup fixed on a handle, used for clearing a blocked pipe by means of suction （疏通管道的）搋子.

• rally
• ramble
• rambunctious
• ramification
• ramify
• ramp
• rampage
• rampant
• rampart
• ramshackle
• rancid
• rancor
• rancorous
• randomize
• randy
• range
• ranger
• rank
• rankle
• ransack
• ransom
• rant
• rap
• rapacious
• rapacity