Word: kofuns
Part of speech: Noun
Syllables: ko
funs
Definition: Plural of kofun; are megalithic tombs or tumuli in Northeast Asia
Morphemes:
Affix: kofun
Language: en
PoS: Noun
Meaning: A megalithic tomb or tumulus in Japan, often with a distinctive keyhole-shaped mound.
Etymology Compounds: Affix: 古墳
Language: ja
Decoded: Gu Fen 
Meaning: ancient grave
Affix: -s
Language: en
PoS: Suffix
Meaning: Used to form many pluralia tantum (nouns that are almost or entirely without singular forms).