a feeling of calm satisfaction with your own abilities or situation that prevents you from trying harder

What annoys me about these girls is their complacency - they seem to have no desire to expand their horizons. 这些姑娘让我生气的是她们的自满情绪——她们似乎根本没有扩展知识面的愿望。

There's no room for complacency if we want to stay in this competition! 我们要想在竞争中立足就决不能自满！