The most common and most likely answer to this crossword clue is the 10 letter word RHINOCEROS
I've seen this crossword clue in The Daily Telegraph
R
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O
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S
More clues leading to the result RHINOCEROS
- Putting cash up front, top businessmen bag river beast
- Horny type getting hornier frolicking outside club with sailor
- Annoyed with lag: 60 minutes upset one with thick skin
- Model iron horse, about ton, powerful beast
- Frightful horn is core to identify this animal
- One may charge you for refining Cornish ore
- Thick-skinned type with the potential to be richer soon
- One blindly charging for chore irons pants
- Thick-skinned creature, old crocodile initially in river, emerged without energy
- Creature in river representing horse icon
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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 RHINOCEROS mean?
RHINOCEROS noun- Any of several large herbivorous pachyderms native to Africa and Asia of the five extant species in the three extant genera in the family Rhinocerotidae, with thick, gray skin and one or two horns on their snouts.