a wall (defensive rampart) / a wall (structure built for defense surrounding an area) / a wall (substantial structure acting as side or division in a building)

to have a deep understanding of

Sino-Vietnamese reading of 薔 / Sino-Vietnamese reading of 戕 / Sino-Vietnamese reading of 嬙 / Sino-Vietnamese reading of 檣 / Sino-Vietnamese reading of 牆 / Sino-Vietnamese reading of 祥 / Sino-Vietnamese reading of 詳 / Sino-Vietnamese reading of 庠 / Sino-Vietnamese reading of 檣 / Sino-Vietnamese reading of 翔

(computing) firewall

to give a detailed report or commentary on an incident

explicit; clear

clear and thorough

wall newspaper

(of electrical wires) inside a wall / (of furniture) placed in a hole on a wall

knowledgeable (about a particular subject)