allowing communication in only one direction at a time, or in telegraphy allowing only one message over a line at a time; "simplex system"
一度に一方向のみ情報のやり取りができる、または電信で一回線で一度に1つのメッセージのみ可能なさま
simplex
having only one part or element; "a simplex word has no affixes and is not part of a compound--like `boy' compared with `boyish' or `house' compared with `houseboat'"