The most common and most likely answer to this crossword clue is the 7 letter word MIMOSAS
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Buddy explains!
The straight part
We know that "They have yellow flowers/America, Buck’s fizzes" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case they have yellow flowers/america, buck’s fizzes = mimosas.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 MIMOSAS mean?
MIMOSAS noun- A plant belonging to the genus Mimosa usually found in tropical climates, their leaves are usually prickly and sensitive to touch or light, and have small white or pink flowers.
- Albizia species (silk tree, pink siris).
- Acacia species.
- A cocktail consisting of half champagne and half orange juice.