set list {{12 11} {12 13} {12 12} {11 14} {13 12}} puts [lsort -index 1 $list] puts [lsort -index 0 [lsort -index 1 $list]] {12 11} {12 12} {13 12} {12 13} {11 14} {11 14} {12 11} {12 12} {12 13} {13 12}