to think or guess that the amount, cost or size of sth is smaller than it really is 低估；对…估价不足◆They grossly underestimated the costs involved. 他们严重低估了所需成本。◆The scale of the challenge we face should not be underestimated. 我们不应该低估所面临挑战的艰巨性。
to not realize how good, strong, determined, etc. sb really is 低估…的价值◆It would be unwise to underestimate our rivals. 低估对手是不明智的。