The most common and most likely answer to this crossword clue is the 7 letter word STRATUM
I've seen this crossword clue in The Sunday Telegraph
S
T
R
A
T
U
M
More clues leading to the result STRATUM
- Little boy’s upset stomach leading to bed
- A point in society setting up arts corporation
- Problem swallowing dessert when lying back in bed
- Group in society mostly keeping quiet about ne’er-do-well
- Problem eating pastry up in a layer
- Traumatised, with no idea about level
- Tot eats food item sitting up in rocky bed
- In casual style, play keeping at a certain level
- Problem outside restaurant for rock band
- Loose women going about with little hesitation – group of a certain class
Buddy explains!

The straight part
We know that "bed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bed = stratum.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 STRATUM mean?
STRATUM noun- One of several parallel horizontal layers of material arranged one on top of another.
- A layer of sedimentary rock having approximately the same composition throughout.
- Any of the regions of the atmosphere, such as the stratosphere, that occur as layers.
- A layer of tissue.
- A class of society composed of people with similar social, cultural, or economic status.
- A layer of vegetation, usually of similar height.
- The level of accuracy of a computer's clock, relative to others on the network.