บางกอก

Believed to be from บาง (baang, “community or polity located near a narrow or small watercourse, or at the place used to such a watercourse”) +‎ กอก (gɔ̀ɔk, “olive”), as olives were cultivated in the area. The name has been called since Ayutthaya period by foreigners. (Du Royaume de Siam spells Bancock/Bancok.)

บางกอก • (baang-gɔ̀ɔk)

1. (now informal) Bangkok (the capital city of Thailand; province of Thailand)

• The area was generally called Bangkok until it was made the capital city of the Rattanakosin Kingdom (now Thailand) in 1782 and a ceremonial name, กรุงเทพมหานคร อมรรัตนโกสินทร์ มหินทรายุธยา มหาดิลกภพ นพรัตนราชธานีบูรีรมย์ อุดมราชนิเวศน์มหาสถาน อมรพิมานอวตารสถิต สักกะทัตติยวิษณุกรรมประสิทธิ์ (grung-têep-má-hǎa-ná-kɔɔn à-mɔɔn-rát-dtà-ná-goo-sǐn má-hǐn-tá-raa-yút-tá-yaa má-hǎa-dì-lòk-póp nóp-pá-rát-râat-chá-taa-nii-buu-rii-rom ù-dom-râat-chá-ní-wêet-má-hǎa-sà-tǎan à-mɔɔn-pí-maan-à-wá-dtaan-sà-tìt sàk-gà-tát-dtì-yá-wít-sà-nú-gam-bprà-sìt), was given to it.
• The ceremonial name is shortened as กรุงเทพมหานคร (grung-têep-má-hǎa-ná-kɔɔn), which now serves as the formal name of Bangkok. This shortened name can again be shortened as กรุงเทพฯ (grung-têep).

• (endonym, formal, colloquial) Krung Thep, Krungthep , Krung Thep Maha Nakhon (official since 1972)