everyone; the public; members of the public
Polite expression used to address or refer to people in society at large, often in announcements, apologies, or formal messages.
We sincerely apologize for causing trouble to everyone in the public.
世間の皆様のご支援に感謝いたします。
We are grateful for the support of the public.
皆様 is a general polite 'everyone', while 世間の皆様 specifically refers to the public or society at large, often in formal public-facing contexts.
世間 means 'society' or 'the world of people', but 世間の皆様 is a fixed polite phrase addressing the public collectively.
Compound of 世間 (society, the world) + の (possessive particle) + 皆様 (polite 'everyone'). A set phrase used in formal public communication.