fifth wheel

IPA(Pronunciation)

/ˌfɪfθ ˈʍiːl/

Noun

US historical idiomatic informal

(road transport) A type of trailer hitch, which consists of a horseshoe-shaped plate on a multidirectional pivot, with a locking pin to couple with the kingpin of a truck trailer.

Japanese Meaning

（道路輸送）トラックとトレーラーを連結するための装置。多方向に可動する軸上に設置された馬蹄形のプレートと、キングピンを固定するためのロックピンを備えている

What is this buttons?

The truck's fifth wheel engaged smoothly with the trailer's kingpin, securing the load for the long haul.

Google Translation / DeepL Translation

トラックのキングピンと結合する馬蹄形のトレーラーヒッチがトレーラーにスムーズに連結し、長距離輸送の荷物を確実に固定した。

Details

Sense（1）

(road transport) A type of trailer hitch, which consists of a horseshoe-shaped plate on a multidirectional pivot, with a locking pin to couple with the kingpin of a truck trailer.

Sense（2）

In full, fifth-wheel trailer: a large caravan or travel trailer that is connected to a pickup truck for towing by a hitch similar to the one described in sense 1 located in the center of the truck's bed.

Fifth-wheel hitching is a simple affair compared to trailer coupling. Choose a quality hitch and don't overburden an inadequate pickup truck with a big fifth wheel and you're almost in business.

Google Translation / DeepL Translation

Details

Sense（3）

(road transport, historical) A horizontal wheel or segment of a wheel above the front axle and beneath the body of a carriage, forming an extended support to prevent it from overturning.

Full fifth-wheels have become quite frequent of late, and it may not be out of place to make a few remarks on their merits as compared with half fifth-wheels. With the exception of heavy coaches and rockaways, nearly all vehicles were until lately made with half fifth-wheels; but at present we find nearly all the different kinds of work, such as landaus, clarences, coaches, landaulets, T-carts, and coupés, made with full fifth-wheels.

Google Translation / DeepL Translation