noun
minor success; small achievement
Refers to a modest or limited success, often contrasted with greater ambitions. Can carry a slightly humble or self-deprecating tone.
彼は小成に甘んじることなく、さらに大きな目標を目指した。
He wasn't satisfied with minor success and aimed for an even bigger goal.
小成を積み重ねることが、やがて大成につながる。
Accumulating small successes will eventually lead to great achievement.