freeze-up

Deverbal from freeze up.

freeze-up (plural freeze-ups)

1. The blocking of pipes due to freezing.
2. A period of extremely cold, freezing weather.
   • 1962 December, “Talking of Trains: Point heaters on the S.R.”, in Modern Railways, page 371:

     The heaters, the S.R. now says, will "help tremendously" if there is severe snow and ice—a welcome change of tune from last winter, when the Region was countering criticism of its operation during the January freeze-up with a bland defence of existing precautions [...].

3. (seasons, time) The start of the time when surface waters are frozen over.

• (antonym(s) of “seasons”): breakup

• “freeze-up”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.