• adbhutam — amazing
  Repeats from verse 15. The chapter brackets the bow-incident with adbhuta-rasa — the Lord's action is the textbook example of the sthāyī-bhāva 'wonder' (vismaya). Rūpa Gosvāmī's rasa-śāstra would later codify this.
• vīryam — heroic deed
  From √vīr — to be heroic. One of the six aiśvaryas (jñāna, śakti, bala, aiśvarya, vīrya, tejas). The verse uses the Bhāgavata's technical lexicon to mark what the citizens witnessed.
• tejaḥ — strength, brilliance
  From √tij — to be sharp, to flash. Tejas is the visible aura of power. Gauḍīya commentators note that Kṛṣṇa's tejas, normally veiled, was permitted to flash here precisely so the city would later recognize Him.
• prāgalbhyam — boldness
  From pragalbha — bold, mature. The Bhāgavata catalogues the qualities visible to the city. Gauḍīya note: prāgalbhya is one of the gopī-nāyaka qualities Rūpa Gosvāmī enumerates in Ujjvala-nīlamaṇi — a sambhoga-nāyaka trait shining here in a martial register.
• vibudha-uttamau — two of the best of demigods
  Contiguous compound: vibudha (wise one, demigod) + uttamau (best, dual). The citizens' mistaken classification. Gauḍīya commentary: they place Kṛṣṇa within the deva-category — a half-step toward truth, the full truth being Bhagavān, source of devas.

• Where have you settled for 'demigod-level' explanations of what is actually Kṛṣṇa Himself?
• How could your estimate of the Lord be quietly raised?

Witnesses to a miracle reach for the only category they have — 'these must be gods.' Mathurā's citizens have the right intuition with the wrong taxonomy. The Bhāgavata records their guess because right intuition without correct frame is still the first step.