Blow the whistle on and Rat on

---

Rat on and blow the whistle on are semantically related In some cases you can use "Rat on" instead a verb "Blow the whistle on".

Rat on verb – To give information (as to the authorities) about another's improper or unlawful activities.

---

Blow the whistle on and rat on are semantically related in tell on topic. Sometimes you can use "Blow the whistle on" instead a verb "Rat on". informal substitute