The most common and most likely answer to this crossword clue is the 7 letter word IMAGERY
I've seen this crossword clue in The Guardian
I
M
A
G
E
R
Y
More clues leading to the result IMAGERY
- German spy's confession perhaps lacking right figures of speech
- Pictures the writer's mature lines
- India has wise man with lines offering pictorial language
- Mental visions one girl receives bring ease at last
- Visualisation of shimmering mirage at the end of the valley
- Dream I am long time on railway
- Pictures of Good Queen Bess captured in one month
- Gay Emir concocted descriptive language
- Figurative writing, picture on line
- One line about dirty game raises mind pictures
Buddy explains!

The straight part
We know that "Visualisation/Visualisation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case visualisation/visualisation = imagery.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 IMAGERY mean?
IMAGERY noun- The work of one who makes images or visible representation of objects.
- Imitation work.
- Images in general, or en masse.
- Unreal show; imitation; appearance.
- The work of the imagination or fancy; false ideas; imaginary phantasms.
- Rhetorical decoration in writing or speaking; vivid descriptions presenting or suggesting images of sensible objects; figures in discourse.