ku-adjective (archaic)
Archaic ku-adjective for blue or azure. In classical Japanese, 青し could also cover greenish hues, but this sense focuses on blue.
古典では「青し」と書いて「あおし」と読み、空や海の色を表した。
In classical texts, 青し was read as あおし and described the color of the sky or sea.
ku-adjective (archaic)
Archaic ku-adjective for green. Historically, 青 covered both blue and green; this sense is distinct from modern 青い.
古語の「青し」は、草木の緑色を指すこともあった。
The archaic 青し could also refer to the green of plants.
ku-adjective (archaic)
Archaic ku-adjective for a pale or grayish complexion, often used in reference to facial color. Used in reference to facial color.
ku-adjective (archaic)
Archaic ku-adjective for unripe or inexperienced, similar to modern 青い in figurative use.
The expression 顔色青し is an old-fashioned way to describe a pale face.
青し is an old way to describe an unripe fruit or an inexperienced person; modern Japanese uses 青い.