To snap one's fingers

To lightly strike the thumb with the finger. Or: to produce a sound by rubbing the thumb against the base of the index finger.

("He asked to be comforted by the flowers of the priestly house, preparing before him a finger of sorrow, and they said to him, "The high priest's men are a pillar, and he has expired once on the floor, and they will keep him busy until the time of the slaughter arrives" - Yoma 1:7, and so: "With a finger of sorrow - the red finger of the assembly. And with a tongue of sorrow. It is a sorrow, as if to say the sorrow of the assembly The samukhah was made by the members of the assembly with the finger of the samukhah, and it fell and struck on his head and made a sound so loud that a high priest would not sleep." - Rabbi Obadiah of Bartenura, Maschet Yoma, Chapter 1)

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