The most common and most likely answer to this crossword clue is the 2 plus 5 letter word IN TRAIN
I've seen this crossword clue in The Times
I
N
T
R
A
I
N
More clues leading to the result IN TRAIN
- Happening to need tip after missing hot shower
- … Having taken alternative transport, making progress
- Making progress, old man leaves paint drops
- In the shower he gets scrubbed, making progress
- Where a Yorkshireman needs his umbrella when under way?
- Revolutionary new independent school is up and running
- Where proverbial annoying mobile user is well organised!
- On board coach under way
- Going on popular means of transport
- En route by land, it’s already started
Buddy explains!
The straight part
We know that "Happening" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case happening = in train.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.