i-adjective
hard to reach; difficult to attain
Literary or formal expression meaning something is difficult to achieve or reach. Often used in written language or formal speech.
その目標は及び難いものだ。
That goal is hard to attain.
彼の学識には及び難い。
His scholarship is difficult to match.
Standard kanji spelling using 難い for 'difficult to'.
Kana spelling is common when the kanji 難 is considered difficult or when emphasizing the reading.
Compound of 及び (continuative form of 及ぶ 'to reach') + 難い (suffix meaning 'difficult to'). The exact historical derivation is uncertain, but the construction follows a common pattern for expressing difficulty.