The most common and most likely answer to this crossword clue is the 11 letter word ICE-BREAKER
I've seen this crossword clue in The Guardian
I
C
E
-
B
R
E
A
K
E
R
More clues leading to the result ICE-BREAKER
Buddy explains!
The straight part
We know that "Relaxing preparation/frees communications, 19" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case relaxing preparation/frees communications, 19 = ice-breaker.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 ICE-BREAKER mean?
ICE-BREAKER noun- A ship designed to break through ice so that it, or other ships coming behind, can navigate on frozen seas.
- A game, activity, humorous anecdote, etc., designed to relax a group of people to help them get to know each other.
- A lively song and dance routine at the start of a musical.