The most common and most likely answer to this crossword clue is the 9 letter word EXTENSION
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More clues leading to the result EXTENSION
- Building work noise dealt with next
- Stretching, stress now gone?
- Once strain, creating annexe?
- Wing added to house without anxiety
- No. sixteen fouled in extra time
- 1, 6 and 10 shuffled for switchboard number
- Development in old conflict
- No longer facing stress, additional time being granted
- Development in old dispute
- Old strain in appendix
Buddy explains!

The straight part
We know that "Wing added to house" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wing added to house = extension.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 EXTENSION mean?
EXTENSION noun- The act of extending; a stretching out; enlargement in length or breadth; an increase
- The state of being extended
- That property of a body by which it occupies a portion of space (or time, e.g. "spatiotemporal extension")
- A part of a building that has been extended from the original
- Capacity of a concept or general term to include a greater or smaller number of objects; — correlative of intension.
- A written engagement on the part of a creditor, allowing a debtor further time to pay a debt.
- The operation of stretching a broken bone so as to bring the fragments into the same straight line.
- An exercise in which an arm or leg is straightened against resistance.
- A simple offensive action, consisting of extending the weapon arm forward.
- A numerical code used to specify a specific telephone in a telecommunication network.
- A file extension.
- An optional software component that adds functionality to an application.
- The set of tuples of values that, used as arguments, satisfy the predicate.
- (grammar) A kind of derivative morpheme applied to verbs in Bantu languages.