An Etymological Dictionary of Astronomy and Astrophysics

1. To collect into a mass or pile; → accumulate.
   

2. To gather for oneself; collect as one’s own (Dictionary.com).

Etymology (EN): M.E., from O.Fr. amasser, from à “to,” → ad-, + masser “to gather in mass,” → mass.

Etymology (PE): Anbâštan, anbârdan “to fill, to replete,” from Mid.Pers. hambāridan “to fill;” from Proto-Iranian *ham-par-, from prefix ham-, → com-, + par- “to fill;” cf. Av. par- “to fill,” parav-, pauru-, pouru- “full, much, many;” O.Pers. paru- “much, many;” Mid.Pers. purr “full;” Mod.Pers. por “full, much, very;” PIE base *pelu- “full,” from *pel- “to be full;” cf. Skt. puru- “much, abundant;” Gk. polus “many,” plethos “great number, multitude;” O.E. full.