pencil push-up
n.— «One method requires a patient to practice converging on a near target or object —turning his or her eyes inward—at home using a procedure called pencil push-ups (so named because the classic object to focus on was the point of a pencil).» —“Treatment available for eyes that don’t function as a team” Waterloo Cedar-Falls Courier (Iowa) Oct. 4, 2006. (source: Double-Tongued Dictionary)
Further reading
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