noun
diversion; pastime; something done to kill time
Refers to an activity done casually to pass the time, often with the hands, such as doodling or playing with a small object. The word is somewhat literary and not an everyday term; 暇つぶし is more common in casual speech.
See also: 手慰み
彼は会議中、手遊びにペンで紙に落書きをしていた。
During the meeting, he was doodling on paper with a pen as a diversion.
Compound of 手 (hand) and 遊び (play, diversion). The reading すさび is an older form of 遊び, giving the word a classical feel.