The definition of friend can be explained in many ways. Here are some common definitions:
1. Friends are people who trust, care and support each other. This relationship is usually based on common interests, experiences, values, etc.
2. A friend is a person who often contacts, helps each other, and shares joys and sorrows in daily life. This relationship is usually based on mutual understanding, respect and trust.
3. A friend is a person who has a positive influence on himself, can help him grow and support him to achieve his goals. This relationship is usually based on a common vision, philosophy, goals, etc.
In short, the definition of friend can vary from person to person, but the core features usually include trust, care, support and mutual help. In the relationship of friends, both parties should respect, tolerate, understand and support each other to jointly create a better interpersonal relationship.