yoga with grace

तत्र प्रत्ययैकतानता ध्यानम्

tatra pratyayaikatanata dhyanam

Dhyana is being in that state where thoughts are steadily flowing.

Yoga Sutras of Patanjali, 3.2

tatra = in that
pratyaya = thoughts
ika = one
tanata = continued flow
dhyana = meditation