عَثْمٌ

verbal noun of 1 [q. v.]. (TA.)

جُبِرَتْ يَدُهُ عَلَى عَثْمٍ means عَلَى عُقْدَةٍ, (S and O in article عقد,) [i. e. His arm was set and joined unevenly,] so as to form a node, or protuberance, like a swelling, not so hard as bone. (ISk, L in article اجر.)