The most common and most likely answer to this crossword clue is the 12 letter word IMPOVERISHED
I've seen this crossword clue in The Daily Telegraph
I
M
P
O
V
E
R
I
S
H
E
D
Buddy explains!
The straight part
We know that "deprived of necessities" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deprived of necessities = impoverished.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 IMPOVERISHED mean?
IMPOVERISHED verb- To make poor.
- To weaken in quality; to deprive of some strength or richness.
- To become poor.
- Reduced to poverty.
- Having lost a component, an ingredient, or a faculty or a feature; rendered poor in something; depleted.