1
the undercarriage of [vehicle]
指汽车等车辆时，undercarriage 常译作“底盘”。
The undercarriage of the car was scratched by a rock.
汽车的底盘被石头刮花了。
底盘
undercarriages — plural of undercarriage
先理解核心含义，再看它在真实句子里的用法。
底盘
the framework under a vehicle that supports its body
The undercarriage of the car was scratched by a rock.
汽车的底盘被石头刮花了。
陆地车辆(如汽车、卡车、厢式货车、四轮马车等)的支撑结构框架。
The supporting structural framework of a land vehicle (such as a car, truck, van, wagon, etc).
飞机的起落架。
The landing gear of an aircraft.
He crawled under the old car to check the undercarriage for damage.
他爬到旧车下面检查底盘是否受损。
A thick layer of mud had built up on the undercarriage of the tractor.
拖拉机的底盘上积了厚厚一层泥。
The mechanic advises spraying the undercarriage with oil every winter to prevent rust.
技师建议每年冬天给底盘喷油以防生锈。
指汽车等车辆时，undercarriage 常译作“底盘”。
The undercarriage of the car was scratched by a rock.
汽车的底盘被石头刮花了。
指飞机时，undercarriage 通常指“起落架”，常用所有格结构。
The plane's undercarriage was damaged during landing.
飞机的起落架在着陆时受损了。
Not this
The jet has a undercarriage that folds into the fuselage.
Use this
The jet has an undercarriage that folds into the fuselage.
“undercarriage” 以元音音素 /ʌ/ 开头，不定冠词应用 an 而不是 a。中文没有冠词，学习者容易按字母 u 误用 a。
Not this
The pilot extended the chassis before landing.
Use this
The pilot extended the undercarriage before landing.
汉语的“底盘”可对应 chassis 或 undercarriage，但飞机的起落架应称 undercarriage；chassis 指车辆底盘框架，不指可收放的起落架。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
可收放式起落架
The pilot lowered the retractable undercarriage before landing.
飞行员在着陆前放下可收放式起落架。
飞机起落架
The aircraft undercarriage must be inspected regularly for wear.
飞机起落架必须定期检查磨损情况。
主起落架
The main undercarriage absorbs most of the impact on touchdown.
主起落架在着陆时吸收大部分冲击力。
汽车底盘
Salt can corrode the car undercarriage in winter.
冬天盐分会腐蚀汽车底盘。
底盘损坏
The mechanic found undercarriage damage caused by rough roads.
机械师发现粗糙路面造成的底盘损坏。
Use undercarriages naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
under（在下方）+ carriage（车架）→ 车身底下的车架就是“底盘”；飞机下方收放的轮架则是“起落架”。
语域：formal 常见场景：车辆维修与检测、汽车技术说明 undercarriage 表示“底盘”时多用于较正式的车辆或机械场景，通常出现在维修、检测和技术说明中；日常口语里较少使用，因此这里选 formal 比较稳妥。
undercarriage 读作 /ˌʌndərˈkærɪdʒ/，重音在 -car-。与 carriage /ˈkærɪdʒ/、marriage（英式 /ˈmærɪdʒ/）押韵；注意美式 marriage 读 /ˈmerɪdʒ/，不再押韵。结尾同为 -age 的 luggage /ˈlʌɡɪdʒ/、average /ˈævərɪdʒ/、heritage /ˈherɪtɪdʒ/、cabbage /ˈkæbɪdʒ/ 都读 /ɪdʒ/，但重音元音不同，不押韵。
Dictionary facts from ECDICT, WIKTIONARY.