Landolt ring
[医] 朗多耳氏环
🧩 词语组成解析
[人名] 兰多尔特
ring
[riŋ]
n. 戒指，指环;铃声，钟声;环形物;拳击场;
vt. 形成环状;环绕;使（例如铃）响;打电话给;
vi. 按铃，敲钟;回响;成环形;
🗣️ 情景例句
Danger.
小心，危险。
No mill, no meal.
不磨面就没有面包吃。
it was not long before its use as the uniquely recognizable broadcasting frequency for interstellar communication was suggested.
提出把它作为星际间唯一可辨认的广播频率就为期不远了。