BṚHADĀRAṆYAKA UPANISHAD · 3.2.3

वाग् वै ग्रहः ।
स नाम्नातिग्रहेण गृहीतः ।
वाचा हि नामान्य् अभिवदति ॥

vāg vai grahaḥ ।
sa nāmnātigraheṇa gṛhītaḥ ।
vācā hi nāmāny abhivadati ॥

'Speech (vâk) is one Graha, and that is seized by name (nâman) as the Atigrâha, for with speech one pronounces names.

F. Max Müller · The Upanishads, Sacred Books of the East 15 (1884)