便是
biànshì · HSK 6
even if
便 = convenient/then + 是 = is; 'then it is (so)' → even if
便 (biàn) often means 'then/just' as a connector, and 是 means 'is'. Together 便是 literally reads 'then is (the case)', a classical/formal way to say 'even if' or 'precisely is'.
便 — person 亻 + change 更
A semantic compound: 亻(person) beside 更 (to change/replace). The original sense was a person making things easier or more convenient by adjusting them. From 'convenient' it extended to 'then/thereupon' (biàn) and to bodily 'discharge' (as in 大便).
是 — sun 日 + 正 (correct/upright)
Originally a compound suggesting 'the sun 日 directly overhead'—straight, correct, true. From this concrete sense of 'right' or 'this very thing,' 是 came to mean 'this' as a demonstrative, and later the modern copula 'to be / is.' The 'correct' meaning survives in words like 是非 (right and wrong).