Grin/ɡrɪn/ Definition 1 of 3Pro Tip 1/3Joyful Context Use 'grin' when describing scenes with joy, amusement, or satisfaction. Watching the puppies play, she couldn't help but grin. Pro Tip 2/3Mischievous Nuance 'Grin' may imply a playful, mischievous attitude when paired with certain contexts. He grinned mischievously as he planned the surprise. Pro Tip 3/3Visible Teeth A 'grin' specifically involves showing teeth, unlike a regular smile. The proud mother grinned at her child's performance.