The most common and most likely answer to this crossword clue is the 5 letter word REFER
I've seen this crossword clue in The Guardian
R
E
F
E
R
More clues leading to the result REFER
- Direct football official about backs
- Direct favour initially ignored
- Consult match official here in middle
- Point in either direction?
- Bring up cold cargo ship whilst offloading first of three
- Would rather, having no power to pass on
- Send on tablet stolen from joint
- Look up, one way or the other
- Pass on way up and down
- Send for information about opening of festival by the Queen
Buddy explains!

The straight part
We know that "Send on" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case send on = refer.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 REFER mean?
REFER verb- To direct the attention of.
- To submit to (another person or group) for consideration; to send or direct elsewhere.
- To place in or under by a mental or rational process; to assign to, as a class, a cause, source, a motive, reason, or ground of explanation.
- (construed with to) To allude to, make a reference or allusion to.
- (grammar) To be referential to another element in a sentence.
- To address a specific location in computer memory.
- Required to resit an examination.