野心 typically carries a negative connotation - overreaching or selfish ambition. For positive ambition, use 雄心 (xiōngxīn) or 抱负 (bàofù) instead. Common phrase: 野心勃勃 (yěxīn-bóbó, wildly ambitious).
memory
A wild (野) heart (心) - ambition that is untamed and unchecked, like a beast that can't be controlled.
