After reading MB OC 301:17:65 (thanks, YDK!) I am baffled by a nagging question regarding Modern Hebrew and Biblical Hebrew. Eliezer Ben-Yehudah is known to have revitalized Hebrew, in part by taking Biblical and post-Biblical (often Mishnaic and/or Rabbinic) Hebrew words, and sometimes Aramaic words, and adapting them to modern uses. But there are words that are not new to the world, and certainly could not have been new to our ancestors, which he apparently adapted from the classical sources because he could not find evidence of them there but found similar words that could be made to apply. The example I'm trying to understand is the Hebrew word for "ice".
In the Mishnah Berurah above why did the M"B need to describe ice as "water which has frozen"? Furthermore, why did he have to Hebraicize the Aramaic word for "freeze"? Is there no classical Hebrew word for "ice" or even "freeze"? According to http://www.mechon-mamre.org/p/pt/pt0131.htm "קֶרַח" translates as "frost". According to http://en.wiktionary.org/wiki/גלד the word "גלד" is Aramaic for "freeze" and Hebrew (presumably modern) for "scab". I have also seen elsewhere in my search today that "גלד" is also used in the context of congealing (I believe in Hebrew).
Is there no other classical Hebrew source for a word that translates directly as "ice"? It seems almost inconceivable that our ancestors did not have a word for this. Is it just that the word is unknown because our sources are limited to Biblical and post-Biblical writings?