pal
A close friend you like spending time with.
A pal is a friend, someone you enjoy spending time with and can count on. When you call someone your pal, you're saying they're someone you like and trust, closer than a casual acquaintance. You might have pals from your soccer team, pals from your neighborhood, or pals you've known since kindergarten.
The word has a casual, warm feeling to it. You might say “Thanks, pal” to a friend who helped you carry your books, or “Let's go, pals!” when gathering your friends for a game. It's friendlier and more personal than just saying “friend,” though it means basically the same thing.
People sometimes use pal when talking to someone they don't actually know well, like when a store clerk says “Can I help you, pal?” In these cases, it's just a friendly way of addressing someone, not a claim of actual friendship.
As a verb, the phrase pal around means to spend time together as friends. If you pal around with someone, you hang out with them regularly, doing things you both enjoy. Close friends who do everything together are sometimes called pals.