Śrīmad-Bhāgavatam 5.21.6
యావద్దక్షిణాయనమహాని వర్ధన్తే యావదుదగయనం రాత్రయ: ॥ ౬ ॥
yāvad dakṣiṇāyanam ahāni vardhante yāvad udagayanaṁ rātrayaḥ.
[yaavad dakshinaayanam ahaani vardhante yaavad udagayanam raatrayah.]
Word-for-word
yāvat
—
until
dakṣiṇa-ayanam
—
the sun passes to the southern side
ahāni
—
the days
vardhante
—
increase
yāvat
—
until
udagayanam
—
the sun passes to the northern side
rātrayaḥ
—
the nights.
Blended reading (Sanskrit + English inline)
yāvad dakṣiṇāyanam ahāni vardhante yāvad udagayanaṁ rātrayaḥ.
yāvat
until
dakṣiṇa-ayanam
the sun passes to the southern side
ahāni
the days
vardhante
increase
yāvat
until
udagayanam
the sun passes to the northern side
rātrayaḥ
the nights.
Until the sun travels to the south the days grow longer, and until it travels to the north the nights grow longer.
Gauḍīya Ācāryas
Viśvanātha Cakravartī Ṭhākura
Gauḍīya
Translation
Until the sun travels on the southern course, the days grow longer, and until it travels to the northern course, the nights grow longer.
Yāvad dakṣiṇāyanam means from uttarāyaṇa until dakṣiṇāyana.
My note
Source: vedabase.io