The most common and most likely answer to this crossword clue is the 4 letter word LASH
L
A
S
H
More clues leading to the result LASH
Buddy explains!

The straight part
We know that "slow in some places" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case slow in some places = lash.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 LASH mean?
LASH noun- The thong or braided cord of a whip, with which the blow is given.
- A leash in which an animal is caught or held; hence, a snare.
- A stroke with a whip, or anything pliant and tough.
- A stroke of satire or sarcasm; an expression or retort that cuts or gives pain; a cut.
- A hair growing from the edge of the eyelid; an eyelash.
- In carpet weaving, a group of strings for lifting simultaneously certain yarns, to form the figure.
- To strike with a lash; to whip or scourge with a lash, or with something like one.
- To strike forcibly and quickly, as with a lash; to beat, or beat upon, with a motion like that of a lash.
- To throw out with a jerk or quickly.
- To scold; or to satirize; to censure with severity.
- To ply the whip; to strike.
- To utter censure or sarcastic language.
- (of rain) To fall heavily, especially in the phrase lash down
- To bind with a rope, cord, thong, or chain, so as to fasten.
- Remiss, lax.
- Relaxed.
- Soft, watery, wet.
- Excellent, wonderful
- Drunk.