The most common and most likely answer to this crossword clue is the 5 letter word ERNIE
E
R
N
I
E
More clues leading to the result ERNIE
- Chap showing interest at first in bird of prey
- Wise picker of bonds
- German I note raised boy
- Boy finding any number in lake
- Wise, maybe, turning up in blue? In red
- Eagle circling round one man
- Man from drive-in restaurant turned up
- Before round half nine – here’s the fastest deliveryman
- Wise number cruncher?
- Chap I don’t know gets one in Berlin up
Buddy explains!

The straight part
We know that "Boy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case boy = ernie.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.