The meaning of "meaning" covers the spectrum from the mundane (What is the meaning of "chthonic?") to the majestic (What is the meaning of life?). The concept of meaning is also used in relation to value or significance, as when we describe experiences as being meaningful or meaningless. The wide-ranging application of the concept of meaning has led to it being viewed as one of the most significant determinants of life quality and even as a basis on which to evaluate the whole of a life. From that perspective there could hardly be anything more important than meaning. However, this last sense of the word fell out of favor in 19th century academic circles due to the fashion for objectivist modes of description. More recently it appears to be returning to favor, due in large part to the failure of cognitive science (and perhaps especially the failure of artificial intelligence research) to specify human experience without having to invoke the slippery concept of meaning.
Meaning is inherently slippery in that it points to a factor in experience that cannot be nailed down to an objective world. Any situation, thing, or activity will generate a response from us humans based, ultimately, on the meaning it has (we make) for us. No matter how precise our listing of its objective and measurable features, these features do not determine our reactions. Instead it is the meaning we make that moves us and motivates our actions. And that meaning may vary considerably from individual to individual, and especially so when those individuals are from different cultures. The real significance of this is that when we invoke the fill richness and profundity of the concept of meaning we are invoking what may well be the most important factor in human life. If this seems too extreme a statement, consider how our joys and our sorrows are determined more by the meaning we give to things than by the things themselves. When have you changed a life disaster into a triumph by finding "new" meaning in what had happened?