The most common and most likely answer to this crossword clue is the 8 letter word PLATONIC
I've seen this crossword clue in The Guardian
P
L
A
T
O
N
I
C
More clues leading to the result PLATONIC
- Caption rewritten to protect leader of Lords Spiritual
- Unromantic pal screwed up introductory note
- Non-physical sport ending early gets boost
- Non-physical complaint head of medicine dismissed wrongly
- Lacking heat, French dish almost postponed
- Excluding congress from scheme, briefly producing tension
- Optical illusion ultimately illusory, not sensual
- Climbing mountain, increasing strength, not going all the way
- Extremely painful, drastic action, not physical
- Climbing mountain with medicine or without it?
Buddy explains!

The straight part
We know that "Unromantic" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unromantic = platonic.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 PLATONIC mean?
PLATONIC adjective- Of or relating to the ancient Greek philosopher Plato or his philosophies.
- Neither sexual nor romantic in nature; being or exhibiting platonic love.