Hanuman Chalisa, Chaupai 3
"mahābīr bikram bajraṅgī" is Chaupai 3 of the Hanuman Chalisa, which Tulsidas wrote in Awadhi. It means: Great hero, valiant, with a body as strong as the thunderbolt, you clear away bad thinking and stay beside good sense. Read it slowly, one half at a time, and say the Awadhi aloud.
महाबीर बिक्रम बजरंगी ।कुमति निवार सुमति के संगी ॥mahābīr bikram bajraṅgīkumati nivār sumati ke saṅgī
Great hero, valiant, with a body as strong as the thunderbolt, you clear away bad thinking and stay beside good sense.
Tulsidas, Hanuman Chalisa, Chaupai 3, Gita Press reading
This line praises Hanuman or speaks to the reader. It does not retell one episode, so there is no single place in the Ramayana to point to.
Awadhi text: Goswami Tulsidas, Gita Press reading, checked against three Gita Press printings and Rambhadracharya's Mahaviri. English meaning and word glosses: Wisdom's own, following the traditional reading, edited by Ankur Shukla.