BT Yev 42b(38) :מסתמיך ואזיל ר׳ אבהו אכתפיה דר׳ תנחום שמעי‏ : (when standing) PN used to continuously lean on the shoulder of PN2, his disciple
See the entire entry for šammāˁ, šammāˁā n.m. servant; disciple