The most common and most likely answer to this crossword clue is the 7 letter word TORSION
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More clues leading to the result TORSION
- Top person's rubbish, turning and twisting
- Dithering about nothing, is turning and twisting
- Twisting in roots is unusual
- Screwing books up — possible complaint of typist working
- Intro’s changed round opening of Oliver Twist
- Rising number consists of deterioration in strain
- Twisting the top-ranked one's deterioration, when you look back
- Twisting in roots, convoluted
Buddy explains!

The straight part
We know that "strain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case strain = torsion.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 TORSION mean?
TORSION noun- The act of turning or twisting, or the state of being twisted; the twisting or wrenching of a body by the exertion of a lateral force tending to turn one end or part of it about a longitudinal axis, while the other is held fast or turned in the opposite direction.
- That force with which a thread, wire, or rod of any material, returns, or tends to return, to a state of rest after it has been twisted; torsibility.
- The stopping of arterial haemorrhage in certain cases, by twisting the cut end of the artery.