The most common and most likely answer to this crossword clue is the 7 letter word ZOOLOGY
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More clues leading to the result ZOOLOGY
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The cryptic/wordplay part
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What does ZOOLOGY mean?
ZOOLOGY noun- The part of biology relating to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct.
- A treatise on this science.