The most common and most likely answer to this crossword clue is the 4 letter word RANT
I've seen this crossword clue in The Guardian
R
A
N
T
More clues leading to the result RANT
- Lively tune followed by tenor
- Violent diatribe coming from Amaranta
- Storm god not lacking in heart
- Rail operated on time
- Spider’s ending with insect in spout
- Declamation from worker against queen?
- Loudly scold scoundrel without the last bit of contrition
- No placid sermon rendered on time
- Television not audible – resident originally turned sound off
- Read note, oddly, as expression of anger
Buddy explains!

The straight part
We know that "spout/spout" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case spout/spout = rant.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 RANT mean?
RANT noun- A criticism done by ranting.
- A wild, emotional, and sometimes incoherent articulation.
- A type of dance step usually performed in clogs, and particularly (but not exclusively) associated with the English North West Morris tradition. The rant step consists of alternately bringing one foot across and in front of the other and striking the ground, with the other foot making a little hop.
- To speak or shout at length in uncontrollable anger.
- To criticize by ranting.
- To speak extravagantly, as in merriment.
- To dance rant steps.