The most common and most likely answer to this crossword clue is the 7 letter word BANDEAU
I've seen this crossword clue in Independent
B
A
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More clues leading to the result BANDEAU
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The straight part
We know that "type of bikini top" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case type of bikini top = bandeau.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 BANDEAU mean?
BANDEAU noun- A band for the hair.
- A band.
- A narrow, tight bra, especially when strapless; hence, any women's top made from a similar band of fabric.