finial
Concise Oxford English Dictionary © 2008 Oxford University Press:
finial /ˈfɪnɪəl, ˈfʌɪn-/
▶noun a distinctive section or ornament at the apex of a roof, pinnacle, or similar structure in a building.
■ an ornament at the top, end, or corner of an object.
– origin ME: from OFr. fin or L. finis ‘end’.
'finial' also found in these Oxford entries:

