|Compliments of Oxford Dictionary's Twitter page|
Can we truly call something that would be unrecognizable as a word without a computer translating it to a visual representation a "word"? What happens when there is no computer between the person writing the "word" and the receiver of the message? Then, an emoji just becomes a sequence of symbols that, alone, make no sense. :-(
We called them "emoticons" until the intervening computer translated them into graphical representations of that sequence.
OD defines "word" as: "A single distinct meaningful element of speech or writing, used with others (or sometimes alone) to form a sentence and typically shown with a space on either side when written or printed." I suppose that an emoji can be considered a word if you use this definition. It seems to meet the requirements. It is a distinct element, it is often (though, not usually) used as part of a sentence. But, is it still a word?
A list of the most recent Words of the Year include a hashtag, and the word "hashtag", itself. While one might fit the definition of "word", I'm not as sure about the other. Just as nominating a specific emoji might make me wonder if OD should start to use it's own definition of "word" when announcing their "Word of the Year".