The most common and most likely answer to this crossword clue is the 5 letter word OVERT
I've seen this crossword clue in The Times
O
V
E
R
T
More clues leading to the result OVERT
- Open a series of deliveries arriving on time
- No secret hole on green
- Out in public, having done time
- Open secret Charlie let out
- Secret initially suppressed in public
- What's obvious all through time
- Finished on time and open to view
- Obvious floating voter
- Deliberate, in the course of time
- Finished before time — that's clear
Buddy explains!

The straight part
We know that "obvious" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case obvious = overt.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 OVERT mean?
OVERT adjective- Open and not concealed or secret.