(Buddhism) the four kinds of suffering: birth, old age, disease and death

the four gods 青龍(せいりょう) (Seiryō), 朱雀(すざく) (Suzaku), 白虎(びゃっこ) (Byakko), 玄武(げんぶ) (Genbu), imported to Japan from Chinese mythology

(collective) the four different states of the sky corresponding to the four seasons

(collective) Clipping of 四天王 (Shitennō, “Four Heavenly Kings”).

(mathematics) geometric mean, specifically, if the variables a, b, c satisfy the relation a:b=b:c, then b is the 幾何中項 of a and c.

(geometry) construction, especially using tools such as ruler and compass

(organic chemistry, dated, deprecated by IUPAC) geometric isomer: a molecule that exhibits geometric isomerism

linguistics

astronomy

physics (as an area of study)