The most common and most likely answer to this crossword clue is the 9 letter word TRAGEDIAN
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More clues leading to the result TRAGEDIAN
- Get in RADA for retraining? One might
- In train wreck, old Sophocles?
- Get in RADA to become such an actor?
- Train crash included elderly actor
- Player, a giant with red dicky
- Actor from Turkey, old chap
- Player was furious, I having taken bronze on the outside
- Actor Tree’s half-cut old Scotsman?
- Actor, tense, became very angry with Scotsman?
- A red giant explodes, becoming a dark star, perhaps?
Buddy explains!

The straight part
We know that "serious actor" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case serious actor = tragedian.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 TRAGEDIAN mean?
TRAGEDIAN noun- An actor who specializes in tragic roles
- A playwright who writes tragedies