The most common and most likely answer to this crossword clue is the 9 letter word BOTANICAL
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More clues leading to the result BOTANICAL
- Unexpected action in lab loosely relating to plants
- Engineer in lab coat dealing with plants
- Sort of garden abandoned to Caliban
- Concerned with bloomers, say, ban coital frolics
- Bad action in laboratory brought about, relating to plant study
- Onset of thrombosis is suppressed by new anabolic drug
- Pertaining to plant's smell and colour – one associated with California
Buddy explains!

The straight part
We know that "relating to plant study" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case relating to plant study = botanical.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 BOTANICAL mean?
BOTANICAL noun- Something derived from a botanical, especially herbal, source
- Of or pertaining to botany; relating to the study of plants