未婚
みこん · mikon · JLPT N1 · na-adj
unmarried
Mi (未) = not yet + kon (婚) = marriage: 'not yet married'.
未 means 'not yet' and 婚 means 'marriage', so 未婚 literally reads 'not yet married', which is the meaning 'unmarried'.
未 — tree 木 with extra short top stroke
未 originally pictured a tree with luxuriant new branches at the top, suggesting tender shoots not yet matured. From this 'not yet ripe' image it came to mean 'not yet' or 'have not.' It is also the 8th Earthly Branch, used in the traditional sexagenary cycle.