The most common and most likely answer to this crossword clue is the 3 letter word MAY
M
A
Y
More clues leading to the result MAY
Buddy explains!

The straight part
We know that "can" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case can = may.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 MAY mean?
MAY verb- To be strong; to have power (over).
- (auxiliary) To be able; can.
- To be able to go.
- (modal auxiliary verb, defective) To have permission to, be allowed. Used in granting permission and in questions to make polite requests.
- (modal auxiliary verb, defective) Expressing a present possibility; possibly.
- (subjunctive present, defective) Expressing a wish (with present subjunctive effect).
- Used in modesty, courtesy, or concession, or to soften a question or remark.
- The hawthorn bush or its blossoms.
- To gather may, or flowers in general.
- To celebrate May Day.
- A maiden.