The most common and most likely answer to this crossword clue is the 7 letter word STUDENT
I've seen this crossword clue in The Times
S
T
U
D
E
N
T
More clues leading to the result STUDENT
- Learner of French involved in dangerous activity
- Learner's clever feat round centre of cul-de-sac
- Trainee in breeding establishment overlooking hospital department
- One learning from on-line books by boss
- Trainee Casanova on Net, getting floppy
- Two low grades in remarkable performance as undergraduate?
- Trainee nurse picked up by boss on time
- Tango in nude’s going wrong – with time one should learn
- Daring act involving extremely desperate undergraduate
- Learner of French taken in by showy performance
Buddy explains!

The straight part
We know that "Trainee" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case trainee = student.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 STUDENT mean?
STUDENT noun- A person who studies or learns about a particular subject.
- A person who is formally enrolled at a school, a college or university, or another educational institution.