An anapodoton (from the Greek anapodosis: "without a main clause") is a rhetorical device related to the anacoluthon. It is a figure of speech or discourse that is an incomplete sentence, consisting of a subject or complement without the requisite object. The stand-alone subordinate clause suggests or implies a subject (a main clause), but this is not actually provided.
As an intentional rhetorical device, it is generally used for set phrases, where the full form is understood, and would thus be tedious to spell out, as in "When in Rome [do as the Romans]." or "If the mountain won't come to Muhammad [Muhammed will go to the mountain]."
Anapodoton is extremely common in Classical Chinese and languages that draw from it, such as Japanese, where a long literary phrase is abbreviated to just a sufficient allusion. For example, Zhuangzi's phrase 井鼃不可以語於海者拘於虛也 "A frog in a well cannot conceive of the ocean." meaning "people of limited experience have a narrow world view" is rendered as 井底之蛙 "A frog in a well" in Modern Chinese, and as I no naka no kawazu (井の中の蛙, A frog in a well) in Modern Japanese, abbreviating I no naka no kawazu taikai o shirazu (井の中の蛙大海を知らず, A frog in a well does not know the great ocean.)
Other uses
It is also said to occur when a main clause is left unsaid due to a speaker interrupting him/herself to revise a thought, thus leaving the initial clause unresolved, but then making use of it nonetheless by recasting and absorbing it into a new, grammatically complete sentence.
Though grammatically incorrect, anapodoton is a commonplace feature of everyday informal speech. It therefore appears frequently in dramatic writing and in fiction in the form of direct speech or the representation of stream of consciousness.
Examples: