Full Idea
We can say that knowing words is knowing how to work out the meanings of sentences containing them. Dictionary definitions are mere clauses in a recursive definition of the meanings of sentences.
Gist of Idea
Knowing a word is knowing the meanings of sentences which contain it
Source
Willard Quine (Russell's Ontological Development [1966], p.76)
Book Reference
Quine,Willard: 'Theories and Things' [Harvard 1981], p.76
A Reaction
Do you have to recursively define all the sentences that might contain the word, before you can fully know the meaning of the word? He seems to credit Russell with the holistic view of sentences (though I think that starts with Frege).