The most common and most likely answer to this crossword clue is the 8 letter word ACTIVATE
I've seen this crossword clue in The Guardian
A
C
T
I
V
A
T
E
More clues leading to the result ACTIVATE
- Prompt report of busy boat crew
- Vessel behind it travelling west during wonderful trip
- Start reviewing it with caveat
- Put in motion part four of drama at Globe finally
- Turn on pretence that is about duty
- Fourth part of play — at end of scene set off
- Set off in vessel heading east after opening scenes
- To start penultimate section of Macbeth, for example, was worrying
- Start to play the part of Evita abroad
- Start off with exploit that is to restrict tax
Buddy explains!

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 ACTIVATE mean?
ACTIVATE verb- To encourage development or induce increased activity; to stimulate.
- To put a device, mechanism (alarm etc.) or system into action or motion; to trigger, to actuate, to set off, to enable.
- To render more reactive; excite.
- To render a molecule reactive, active, or effective in performing its function.
- To render a substance radioactive.
- To hasten a chemical reaction, especially by heating.
- To remove the limitations of demoware by providing a license; to unlock.
- To aerate in order to aid decomposition of organic matter.
- To organize or create a military unit or station.
- To bring a player back after an injury.