forerunner

1. N-COUNT If you describe a person or thing as the forerunner of someone or something similar, you mean they existed before them and either influenced their development or were a sign of what was going to happen. 先驱; 前身; 前兆

...a machine which, in some respects, was the forerunner of the modern helicopter. …一台在某些方面是现代直升飞机的前身的机器。