The most common and most likely answer to this crossword clue is the 8 letter word ASSUMING
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The straight part
We know that "Expecting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case expecting = assuming.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 ASSUMING mean?
ASSUMING verb- To authenticate by means of belief; to surmise; to suppose to be true, especially without proof
- To take on a position, duty or form
- To adopt a feigned quality or manner; to claim without right; to arrogate
- To receive, adopt (a person)
- To adopt (an idea or cause)
- An assumption.
- Haughty; arrogant