tato 'viśan vanaṁ candra
jyotsnā yāvad vibhāvyate
tamaḥ praviṣṭam ālakṣya
tato nivavṛtuḥ striyaḥ
tataḥ - then; aviśan - they entered; vanam - the forest; candra - of the moon; jyotsnā - the light; yāvat - as far; vibhāvyate - as was visible; tamaḥ - darkness; praviṣṭam - entered; ālakṣya - noticing; tataḥ - thereupon; nivavṛtuḥ - they desisted; striyaḥ - the women.
The gopīs entered a part of the forest so dense that even the light of the full moon couldn’t penetrate it. This scene is also described in the Viṣṇu Purāṇa:
praviṣṭo gahanaṁ kṛṣṇaḥ
padam atra na lakṣyate
nivartadhvaṁ śaśāṅkasya
naitad dīdhiti-gocaraḥ
“One gopī said, ‘Kṛṣṇa has entered such a dark part of the forest that we cannot possibly see His footprints. Therefore let us turn back from this area, which even the light of the moon cannot reach.’”