What's the Mind of the Church?

Brethren, Peace and Good to all of you.
A recent conversation in the combox motivates me to answer the question: What is the Mind of the Church?" I got a quick answer from the New Catholic Dictionary:
The Church's attitude and teaching with regard to matters not solemnly defined as dogmas of Faith, but declared by her serious pronouncements and by the teaching of her approved theologians. To think and to act with the Church in matters not solemnly defined, is characteristic of a loyal member of the Church. Lack of respect for the mind of the Church incurs danger of complete loss of Faith.
 This is a great definition of what the matter is, and what we should do about it. We'll do well to understand the Mind of the Church at all times and make her mind our own.