noun which may take the genitive case particle 'no', noun
first in history; unprecedented
Used to describe something that has never happened before in recorded history. Often modifies nouns with の.
This is the first manned landing on Mars in history.
They achieved an unprecedented feat.
Compound of 史上 (しじょう, 'in history') and 初 (はつ, 'first'). The reading はつ is the native Japanese reading for 初.