a cup or bowl: a rounded open vessel for drinking or serving, and by extension the cup-shaped ornaments of the golden lampstand
At its core this word names a physical cup or bowl. It is Joseph's silver cup, hidden in Benjamin's sack and then found there (Genesis 44), and it is the wine vessels set before the Rechabites in Jeremiah 35:5.
The same word names the cup-shaped ornaments on the golden lampstand described in Exodus 25 and 37. The text says these were "made like almond blossoms," each set with a knob and a flower. They are called cups because they had the shape of an open blossom-cup, not because anyone drank from them.
So one word covers both an everyday vessel and a decorative form modeled on its shape. Where size is in view it leans toward a larger bowl or goblet: in Jeremiah 35:5 it stands beside the ordinary drinking cup (כּוֹס), this word naming the serving bowls and כּוֹס the cups poured from them.