必ずしも
かならずしも · kanarazushimo · JLPT N3 · adverb
always
🤷 必 = must + ずしも: must-not-must, so not necessarily
必ず alone means 'without fail' (必 = must). Add しも and pair it with a negative verb: 必ずしも〜ない = 'not necessarily'. Verbal hook: kanarazu means 'certainly', so kanarazushimo means 'certainly... NOT'. It only works with a negative at the end.
必 — heart 心 + slash 丿
Originally depicted a handle or marker driven through something, suggesting a fixed standard. The form was later reanalyzed as 心 (heart) with a stroke through it, reinforcing the sense of inner certainty. It came to mean 'must' or 'certainly'.