Term
Hinder
When play is disrupted by a short-lived event that is not caused by a player. The rally is replayed.
When play is disrupted by a short-lived event that is not caused by a player, such as a ball rolling in from the next court or an insect (Section 2, Definitions). Things that are always there around the court, such as walls, fences, and net posts (permanent objects), do not count as a hinder (Section 2, Definitions). Anyone can call it, and the rally is replayed (9.C.1, 9.C.2, Replay the rally when something gets in the way (hinder)).
See it in a figure
This figure is from the rule "Replay the rally when something gets in the way (hinder)".
How to read the sources: numbers like (8.F.4) are rulebook sections, and links are outside sources. An "Author's note" is the author's personal experience, not an official rule.