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phacodonesis

n. The vibration of the lens accompanying eye movement.

Wikipedia
Phacodonesis

Phacodonesis is the tremulousness or vibration of the lens with eye movement. This is often due to lens subluxation, the incomplete or partial dislocation of the lens, caused by an injury to the eye in which some or most of the zonular fibers are broken. The term originated from phaco- (, lens) + doneo (, to shake to and fro).