letterboxes

英 [ˈletəbɒksɪz]

美 [ˈletərbɑːksɪz]

n.  邮筒，信箱
letterbox的复数

柯林斯词典

• （门上的）信件投递孔；（建筑物入口处的）信箱
  Aletterboxis a rectangular hole in a door or a small box at the entrance to a building into which letters and small parcels are delivered.

in AM, usually use 美国英语通常用 mailbox


• （电视或计算机显示）信箱格式的，上下黑边的，宽屏的
  If something is displayed on a television or computer screen inletterboxformat, it is displayed across the middle of the screen with dark bands at the top and bottom of the screen.