The most common and most likely answer to this crossword clue is the 9 letter word EMBARKING
E
M
B
A
R
K
I
N
G
More clues leading to the result EMBARKING
- The setter having sprung up, cuckoo setting off
- Getting on, this setter is flipping barmy
- Getting on a drug, male gets mad
- This writer’s suffering setback, crazy and getting on
- Setter getting up: sound of setter getting on
- Setting off a dog’s noise after letter
- Dorothy's beloved doggy cries, boarding the Wizard's balloon?
- Emily, talking like a sergeant, getting on board
- Emily imitating dogs getting on board
Buddy explains!

The straight part
We know that "getting on board" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case getting on board = embarking.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 EMBARKING mean?
EMBARKING verb- To get on a boat or ship or (outside the USA) an aeroplane.
- To start, begin.
- To cause to go on board a vessel or boat; to put on shipboard.
- To engage, enlist, or invest (as persons, money, etc.) in any affair.
- An embarkation.