The type–token distinction is relevant to the notion ‘word’ in this way.
Sentences (spoken or written) may be said to be composed of wordtokens,
but it is clearly not word-tokens that are listed in dictionaries. It
would be absurd to suggest that each occurrence of the word next in (1)
merits a separate dictionary entry. Words as listed in dictionaries entries
are, at one level, types, not tokens – even though, at another level, one
may talk of distinct tokens of the same dictionary entry, inasmuch as the
entry for month in one copy of the Concise Oxford Dictionary is a different
token from the entry for month in another copy