signe avant-coureur w języku angielskim

herald [heralds]▼◼◼◼(a harbinger giving signs of things to come)
noun
[UK: ˈhe.rəld] [US: ˈhe.rəld]

canary in a coal mine▼(early indicator)
noun
[UK: kə.ˈneə.ri ɪn ə kəʊl maɪn] [US: kə.ˈne.ri ɪn ə koʊl ˈmaɪn]