久しい
ひさしい · hisashii · JLPT N1 · i-adj
long
ひさしい sounds like 'he's shy' but means long: 'it's been hisashii since we saw each other' = it's been a long time.
久 (ku) means long-lasting, as in 永久. Think of 'long time no see' in Japanese: 久しぶり, from the same root.
久 — person 人 with a stroke marking the back
Originally a pictograph showing a person from behind with a mark indicating moxibustion treatment applied to the back, the original sense of 'cauterize' (now written 灸). It was borrowed phonetically to mean 'long time' or 'enduring,' which became its standard meaning.