mud boat; boat for transporting mud
Literal meaning: a boat used to carry mud, often in construction or dredging contexts.
A mud boat is being used at the construction site.
mud boat (folktale); sinking ship (figurative)
In folktales, a boat made of mud that inevitably sinks; figuratively, a hopeless situation or a doomed enterprise.
The mud boat that appears in old tales sinks right away.
That plan is already a sinking ship.
Variant kanji spelling using 船 instead of 舟.
Compound of 泥 (doro, 'mud') and 舟/船 (fune, 'boat'). The figurative sense comes from the idea of a boat made of mud that cannot stay afloat.