The most common and most likely answer to this crossword clue is the 8 letter word BANISTER
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More clues leading to the result BANISTER
- Rail is straddled by kid
- Rail set in bar coming loose
- Railing is in raillery!
- Rail supporter is overwhelmed by jokes
- Joking about island feature encountered on way up?
- Second-class wine sent back by rail
- Jesting about one’s 1 Across on flight
- St Bernard maybe needing one for road and rail
- Roger ignored Newton and slid up this
- Is jesting about providing support on flight
Buddy explains!

The straight part
We know that "something to slide on" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something to slide on = banister.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 BANISTER mean?
BANISTER noun- The handrail on the side of a staircase.
- One of the vertical supports of a handrail; a baluster.
- To construct a banister
- To act as a banister