eh
Synonym discussion
Sense: interjection/1
All four words are used in informal spoken English to get a reaction from a listener, but they differ in function and politeness. 'Eh' is the most neutral — it can express surprise, ask for repetition, or check agreement depending on tone. 'Huh' is closer to 'eh' for surprise or repetition but sounds slightly more casual and can imply you did not understand. 'Right?' is more explicit: it directly asks the listener to confirm, and works in casual writing too ('You live nearby, right?'). 'Hey' is primarily an attention-getter, not a check for agreement or understanding — you use it to start a conversation or interrupt. In daily conversation, a Canadian speaker might use 'eh' three times in a chat ('Cold out, eh? Eh? You said something? Pretty good, eh?'), while an American would rely more on 'right?' and 'huh' for the same range of functions.
Etymology
A natural exclamation of questioning or surprise that has been part of English since the 1500s. It is likely a spontaneous human sound, like the similar 'eh' found in French, Dutch, and many other languages, rather than a word from a specific root.
First known use
1677
1677, in the meaning defined above