Rasarnavasudhakara 1.326

1.326

atha hāvaḥ-
grīvā-recaka-saṃyukto bhrū-netrādi-vilāsa-kṛt |
bhāva īṣat-prakāśo yaḥ sa hāva iti kathyate ||

Now, flirtatious gesture:
Accompanied by a circular motion of the neck, and producing playful movements of the eyebrows, eyes, and the like,
that emotion which is slightly manifested is termed flirtatious gesture.