Strum/strʌm/ Definition 1 of 2Pro Tip 1/3Informal Usage Strumming is typically used in casual or informal settings like campfires and small gatherings. We sang songs while he strummed his ukulele. Pro Tip 2/3Not Just Guitars 'Strum' applies to other string instruments besides guitars, like ukuleles and banjos. She learned to strum a beautiful melody on her new mandolin. Pro Tip 3/3Physical Gesture Strumming involves a sweeping motion across strings, not individual picking. Strum the strings in one fluid motion for a fuller sound.