Комментарии:VEWT 117, KW 431 (without the Korean form), EAS 64, SKE 43, АПиПЯЯ 286. Despite Doerfer's (TMN 3, 122) criticism, the root is certainly common Altaic. In Mong. cf. also reduplicated forms: Khalkha cogcojǯ sū-, Bur. sogsojžo hū- 'to squat', sogsogono- 'to curtsey'. The original meaning must have been 'squat', 'kneel down' - whence 'incline, sink', and further metaphorical developments: 'lose hope', 'die'.