also: かどふだ
noun
doorplate; nameplate; gate pass
A plate or tag attached to a gate or door, typically showing the resident's name or serving as a pass for this word.
門札に名字が書いてある。
The family name is written on the doorplate.
この門札を見せれば中に入れます。
You can enter if you show this gate pass.
表札 is a general nameplate for a house or room, while 門札 specifically refers to one on a gate or door, and can also mean a gate pass.
Compound of 門 (gate) and 札 (tag, plate). The reading もんさつ uses the on'yomi of both characters; かどふだ uses the kun'yomi.