The most common and most likely answer to this crossword clue is the 4 letter word LAID
I've seen this crossword clue in Independent
L
A
I
D
Buddy explains!

The straight part
We know that "Spread" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case spread = laid.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 LAID mean?
LAID adjective- (of paper) Marked with parallel lines, as if ribbed, from wires in the mould.
- To place down in a position of rest, or in a horizontal position.
- To cause to subside or abate.
- To prepare (a plan, project etc.); to set out, establish (a law, principle).
- To install certain building materials, laying one thing on top of another.
- To produce and deposit an egg.
- To bet (that something is or is not the case).
- To deposit (a stake) as a wager; to stake; to risk.
- To have sex with.
- To take a position; to come or go.
- To state; to allege.
- To point; to aim.
- (ropemaking) To put the strands of (a rope, a cable, etc.) in their proper places and twist or unite them.
- To place and arrange (pages) for a form upon the imposing stone.
- To place (new type) properly in the cases.
- To apply; to put.
- To impose (a burden, punishment, command, tax, etc.).
- To impute; to charge; to allege.
- To present or offer.
- To don or put on (tefillin (phylacteries)).