The most common and most likely answer to this crossword clue is the 9 letter word LUBRICATE
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More clues leading to the result LUBRICATE
- “Grease” number disco regularly cuts dead
- Leader’s abandoned guiding rule in ‘tardy’ smear
- Get drunk – Cuba libre
- Car built to run on the ultimate in engine oil
- Badly built car needs a drop of engine oil
- A bit cruel recasting Grease?
- Oil club I rate poorly
- Translated article about principal of using barrels to deliver oil
- *Smooth running of tribunal over college exams at first
- Oil race-built buggy
Buddy explains!

The straight part
We know that "smear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case smear = lubricate.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 LUBRICATE mean?
LUBRICATE verb- To make slippery or smooth (normally to minimize friction) by applying a lubricant.