The most common and most likely answer to this crossword clue is the 5 letter word CLOGS
I've seen this crossword clue in Independent
C
L
O
G
S
More clues leading to the result CLOGS
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The straight part
We know that "blocks" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case blocks = clogs.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 CLOGS mean?
CLOGS noun- A type of shoe with an inflexible, often wooden sole sometimes with an open heel.
- A blockage.
- A shoe of any type.
- A weight, such as a log or block of wood, attached to a person or animal to hinder motion.
- That which hinders or impedes motion; an encumbrance, restraint, or impediment of any kind.
- To block or slow passage through (often with 'up').
- To encumber or load, especially with something that impedes motion; to hamper.
- To burden; to trammel; to embarrass; to perplex.
- To enforce a mortgage lender right that prevents a borrower from exercising a right to redeem.
- To perform a clog dance.