A twirl is when you spin around with your arms out, usually for fun or to show off. It can also mean a turn or movement that isn't straight.
When we say someone's going to give us a twirl, it means they're going to make us dance or move in a fun way - think of a playful parent showing off their kid's dance skills. But sometimes we use twirl as an everyday word too: "I had a big twirl of spaghetti on my fork!" Here we mean just a turn of food, like when you twist a rope and it curls around itself a bit. When you twirl your hair, that means you're turning it around to make a nice, neat coil - so again, a simple movement.
A movement where a person spins round elegantly; a pirouette.
