The most common and most likely answer to this crossword clue is the 6 letter word EMBODY
I've seen this crossword clue in Independent
E
M
B
O
D
Y
More clues leading to the result EMBODY
- Incorporate space by taking in odd edges
- Make material that’s woven by demo
- Contain them by gathering force
- Contain wider space by taking in suburbs of Oxford
- Incorporate large space group
- Epitomise the origins of every mischievous boy or deviant youth
- Incorporate dome by reconstruction
- Give substance to English doctor, oddly prescribing itself
- Cyclops having turn, gets stiff, that’s manifest
- Represent group on the fringes of eco-terrorism
Buddy explains!

The straight part
We know that "Give substance to" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case give substance to = embody.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 EMBODY mean?
EMBODY verb- To represent in a physical or concrete form; to incarnate or personify.
- To represent in some other form, such as a code of laws.
- To comprise or include as part of a cohesive whole; to be made up of.
- To unite in a body or mass.