Causes trouble, annoyance, or concern to someone; problems or hassles.
From uncertain origins, possibly from Irish 'bodhraim' (I deafen) or related to 'bother' meaning 'confusion,' it entered English usage around 1700, likely from Irish English.
What bothers you is entirely cultural—in some countries, being late is no bother at all, while in others it's deeply offensive, showing that 'bother' is actually a complex social negotiation disguised as a simple word.
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