革新
かくしん · kakushin · JLPT N1 · noun
innovation
💡 革 (change, as in 革命 revolution) + 新 (new) = reform or innovation
革 originally meant animal hide, later came to mean change (as in 革命 revolution). 革新 combines change and new, so it means making things new by changing them.
新 — 立 stand + 木 tree + 斤 axe
Originally depicted cutting fresh wood with an axe (斤) from a tree (木), with 辛/立 as the phonetic component. The original meaning of 'firewood' was later written as 薪, while 新 took on the extended sense of 'new' or 'fresh'.