also: びょうひょう
noun
anchor ice; bottom-fast ice
Technical term for ice that forms and remains attached to the bottom of a river, lake, or shallow sea, often in cold climates.
厳冬期には川底に錨氷が発達することがある。
In severe winter, anchor ice can develop on the riverbed.
錨氷の観測には特殊な機器が必要だ。
Special equipment is needed to observe bottom-fast ice.
Compound of 錨 (ikari, 'anchor') and 氷 (kōri, 'ice'), describing ice that is 'anchored' to the bottom. The reading びょうひょう is the Sino-Japanese reading of the same characters.