The most common and most likely answer to this crossword clue is the 5 letter word GELID
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More clues leading to the result GELID
- Freezing, as having lifted top
- Very cold, as eels may be, roughly speaking
- Frozen eel is served like this, I gather
- Frosty starts to General Election leaders’ interactive debates
- Cold bagel idiot’s offering
- Frozen, like eels, say
- Very cold bottoms on freezing ice cap
- Cap put on say, turning icy
- Frigid upper-class girl with little money once
- Delightful out to start with, but very cold
Buddy explains!

The straight part
We know that "Extremely cold" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case extremely cold = gelid.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GELID mean?
GELID adjective- Very cold; icy or frosty.