偉大
いだい · idai · JLPT N3 · na-adj
greatness
🏆 偉 eminent + 大 big = greatness; いだい sounds like ideal
偉 means eminent or outstanding, as in 偉人 (いじん, a great person). 大 means big. An eminent person who is also big in stature has greatness. The sound idai is close to ideal, and greatness is the ideal.
大 — pictograph of a person with arms outstretched
大 is a pictograph showing a person standing with arms and legs spread wide. The outstretched arms suggest 'big' or 'great', extending from the literal image of a large stance to abstract meanings like important or grand. It is one of the oldest characters, found on oracle bones.