To the extent I'm aware, Philosophy is acutely concerned about meaning. Without definitions being crisp and clear progress in thought would be impossible. One could say that a major setback in some philosophical branches is the lack of good definitions.

It's advised that defining, giving meaning to words, follow some accepted guidelines, some of which are:

1. Focus on the essentials
2. Be clear - avoid ambiguity, vagueness, metaphor, obscurity
3. Don't define in negatives when it's possible to be positive
4. Don't make definitions too broad or too narrow
5. Avoid circularity

Given we have to meet the criteria of a good definition above,

What is the definition of ''definition''? Or
What is the meaning of ''meaning''?

I'm no linguist but the question seems problematic, since any attempt to define ''definition'' violates criteria 4 i.e. avoid circularity.

How does philosophy solve this problem?

This is a paradox because we have to know the meaning of ''meaning'' before we can assign it meaning.