Inc crochet meaning refers to the abbreviation for increase, meaning you work two or more stitches into the same stitch to add stitches to your count. I see this abbreviation constantly in amigurumi and hat crown instructions. This guide gives the direct definition and a worked example.

Detailed Explanation
A pattern line reading sc in next 3 sts, inc, repeat around (24) means single crochet across three stitches, then work an increase by placing two single crochet stitches into the next single stitch, repeating the whole sequence around the round.

Frequently asked questions
What does inc mean in a crochet pattern?
Inc stands for increase, meaning you work two stitches into the same stitch to add a stitch to your total count, commonly used when shaping a rounded piece like an amigurumi or hat crown.
Want the decrease equivalent too?
Decreases work the opposite way, combining stitches to remove them from the count.
See the decrease guide