verb / noun
strum
STRUM/strʌm/
A sweep of the fingers or a pick across a stringed instrument's strings.
The musician strums across the guitar's strings.

Etymology
Strum may imitate the sound of fingers sweeping across strings. It originally meant playing unskillfully, then broadened to include casual playing without necessarily implying an unpleasant sound.
In context
we don't have to worry about muting any strings and we can strum all the strings
More examples
- A gentle strum introduced the song.
- He was strumming quietly on the porch.
- The musician used a pick to strum the strings.
Forms
strum · strums · strummed · strumming