The most common and most likely answer to this crossword clue is the 11 letter word IMMEDIATELY
I've seen this crossword clue in The Daily Telegraph
I
M
M
E
D
I
A
T
E
L
Y
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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 IMMEDIATELY mean?
IMMEDIATELY adverb- In an immediate manner; instantly or without delay.
- Directly (as soon as). Indicates that the independent clause describes something that occurs immediately after the dependent clause's referent does.