Echo question

An echo question is a question that directly takes up (or "echoes") part of a declarative sentence made before. It copies an utterance and contains a wh-phrase in situ.

Example
A: I'm going to Nizhnesverdlovsk. B: You're going where?''

Comments
In English, such questions can contain wh-words that occur in situ rather than in initial position. For English, this is therefore sometimes taken as definitional for echo questions.

This type of question is usually considered irrelevant in the discussion of wh-movement (What did John buy?) and wh-in-situ (Who bought what?).

Other languages
German Echofrage

Link
Utrecht Lexicon of Linguistics