open letter

US /ˌoʊ.pən ˈlet̬.ɚ/
UK /ˌoʊ.pən ˈlet̬.ɚ/
"open letter" picture
1.

surat terbuka

a letter of protest or appeal addressed to a particular person or group but intended for general publication

:
The activists published an open letter to the government.
Para aktivis menerbitkan surat terbuka kepada pemerintah.
Her open letter about climate change went viral.
Surat terbukanya tentang perubahan iklim menjadi viral.