• kṣmā-bhṛt-droṇī — valley of a mountain
  Compound: kṣmā (earth) + bhṛt (holder, i.e. mountain) + droṇī (valley, trough). The earth-supporting mountains, ordinarily refuges, are weaponized into prisons. The asura turns śelter into tomb.
• guhāsu — in the caves
  Locative plural of guhā. Caves in śāstra often house yogis and seers; here they become traps. The poet inverts every benign archetype in turn — fire, mountain, cave.
• peśaṣkārī-iva-kīṭakam — as a wasp imprisons a small insect
  Simile from natural history (the mud-dauber wasp). Cited in śāstra also for bhramara-kīṭa-nyāya — the insect that, by constant fear of the wasp, takes on the wasp's form. Here the comparison is just to cruelty; but the nyāya it evokes is itself a Gauḍīya emblem of how dhyāna transforms the meditator.
• dṛptaḥ — audacious, puffed up
  From √dṛp (to be elated, intoxicated with pride). The same root will return in mada-uddhataḥ (v.15). Pride is the chapter's diagnosed root of the demon's career.
• nikṣipya — casting (in)
  From ni- + √kṣip (to throw down into). The body-thrown-into-prison gesture; SB will mirror it in v.25 when Balarāma's bare-hand blow throws Dvivida himself down. Asuric verbs come back on the asura.

• Whom am I 'caving in' through control or contempt?
• Where am I letting someone trap me in a story about who I am?

A wasp paralyzes a caterpillar and seals it in a clay cell, indifferent to its terror — Dvivida does this to whole families, men and women sealed alive into mountain caves. Cruelty in the asura is not heat-of-the-moment; it is a craft, with technique and pride.