"Aspis" ( /ˈæspɨs/; Ancient Greek: ἀσπίς) is the generic term for the word shield. The aspis carried by Greek infantry (hoplites) of various periods is often referred to as a hoplon (Ancient Greek: ὅπλον).
According to Diodorus Siculus:
... and the infantry who had formerly been called "hoplites" because of their heavy shield (aspis), then had their name changed to "peltasts" from the pelta they carried. —Diodorus Siculus. The Library, 15.44.3.Read more about Aspis: Construction