The most common and most likely answer to this crossword clue is the 6 letter word BANTER
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More clues leading to the result BANTER
- Rant be damned, it's playful teasing
- Playful remarks coming from drab anteroom
- Teasing talk is taken away from stair-rail
- Rail is missing from banister
- Repartee from British worker meeting royal lady
- Ridicule getting stake in old train company
- Light repartee featuring in club anteroom
- Joking bartender left the German drunk
- Model in distress starting to raise kid
- Stop condition limited for exchange
Buddy explains!

The straight part
We know that "Rail" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rail = banter.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 BANTER mean?
BANTER noun- Sharp, good-humoured, playful, typically spontaneous conversation.
- To engage in banter or playful conversation.
- To play or do something amusing.
- To tease (someone) mildly.
- To joke about; to ridicule (a trait, habit, etc.).
- To delude or trick; to play a prank upon.
- (Southern and Western) To challenge to a match.