The most common and most likely answer to this crossword clue is the 8 letter word COGITATE
I've seen this crossword clue in The Guardian
C
O
G
I
T
A
T
E
More clues leading to the result COGITATE
- Deliberate deception upset engaging Italian
- Deliberate gait wrongly shown in French side
- Business has private gallery to consider
- Think tooth — it chewed
- Ponder a time in century-old French cottage
- Think about old barrier about sex
- Think about nothing, then stir to depose leader
- Ponder gearwheel, one that’s initially bolted down
Buddy explains!

The straight part
We know that "Think" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case think = cogitate.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 COGITATE mean?
COGITATE verb- To meditate, to ponder, to think deeply.
- To consider, to devise.