The most common and most likely answer to this crossword clue is the 5 letter word HEADS
I've seen this crossword clue in The Sunday Telegraph
H
E
A
D
S
More clues leading to the result HEADS
- Directors on the side of money?
- Takes charge of macho publicity?
- The man with lots of money but not with the bosses
- & 5 & 24 Principals are going to be revolutionary? Expect sackings!
- Call captain makes in ship’s toilet
- Schoolteacher‘s random call?
- Is in charge of gas bills
- Warning, principal’s out of bed!
- Lead shot’s opening floating can?
- Is the boss giving warning in America?
Buddy explains!
The straight part
We know that "Warning" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case warning = heads.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 HEADS mean?
HEADS noun- The part of the body of an animal or human which contains the brain, mouth and main sense organs.
- The topmost, foremost, or leading part.
- (social, metonymy) A leader or expert.
- A significant or important part.
- Headway; progress.
- Topic; subject.
- Denouement; crisis.
- (fluid dynamics) Pressure and energy.
- Fellatio or cunnilingus; oral sex.
- The glans penis.
- A heavy or habitual user of illicit drugs.
- Power; armed force.
- A pair of speakers worn over or in the ears so only the wearer can hear the sound.
- That part of older sailing ships forward of the forecastle and around the beak, used by the crew as their lavatory; still used as the word for toilets on a ship.
- The side of a coin that bears the picture of the head of state or similar.
- Draft scheme of a bill before it is formally introduced to a parliament.
- Tiles laid at the eaves of a house.
- A shouted warning that something is falling from above, mind your heads.
- To be in command of. (See also head up.)
- To come at the beginning of; to commence.
- To strike with the head; as in soccer, to head the ball
- To move in a specified direction.
- To remove the head from a fish.
- To originate; to spring; to have its course, as a river.
- To form a head.
- To form a head to; to fit or furnish with a head.
- To cut off the top of; to lop off.
- To behead; to decapitate.
- To go in front of.
- To get in the front of, so as to hinder or stop; to oppose.
- (by extension) To check or restrain.
- To set on the head.
- High-grade marijuana.