Meaning of the Sanskrit Word: yasam

  yāsām—of which    SB 5.20.3-4, SB 5.20.16
  yāsām—of all of whom    SB 6.6.3, SB 10.6.39-40
  yāsām—of whom (the gopīs)    Adi 17.281, Madhya 9.150
  yāsām—from whose    SB 1.10.30
  yāsām—whose    SB 1.11.36
  yāsām—of those whose    SB 3.14.12
  yāsām—of them    SB 4.3.12
  yāsām—of whom (the daughters)    SB 5.18.15
  yāsām—of all the rivers    SB 5.20.22

Can't find any compound Sanskrit words containing yasam.