Comparative evidence

bʰerǵʰ

• OInd. br̥h- ‘grow great’, ‘grow strong’, ‘increase’ (MW: 735; Whitney 1885: 107)

• OInd. br̥h-/vr̥h- ‘tear’ (MW: 735; Whitney 1885: 107)

Whitney 1885: 107: “The relations of the two roots br̥h- and the connection of some of their Derivatives are not wholly clear”.

Jamison 1983: 97‒98: “There is no confusion in the RV between the initials b and v of the roots br̥h and vr̥hrespectively, although such confusion is widespread in later Sanskrit. <…> Hence, barhayati seems to be the original present of the root br̥h in the RV”.
Derivatives

• OInd. br̥h ‘prayer’ (MW: 735)

• OInd. -barha ‘tail feather’, ‘leaf’ (MW: 722)

• OInd. -bárhaṇa ‘tearing’, ‘pulling out’ (MW: 722)

• OInd. barháṇā ‘strongly’, ‘firmly’, ‘really’, ‘certainly’ (MW: 722)

• OInd. br̥hant ‘large’, ‘wide’ (MW: 735)

• OInd. bráhman ‘sacred word’, ‘spirit’(of the Universe) (MW: 737-738)

• OInd. brahmán ‘devout man’, ‘Brahman’, ‘Brahmanical caste as a body’ (MW: 738)

• OInd. br̥ṃhaṇa ‘making big’ ‘making fat’, ‘making strong’, ‘nourishing’ (MW: 735)

References

Jamison 1983 = Jamison, S.W. Function and Form in the -áya-formations of the Rig Veda and Atharva Veda. Göttingen: Vandenhoeck & Rupert.
MW = Monier-Williams, M. 1899. A Sanskrit-English Dictionary. Clarendon Press.
Whitney 1885 = Whitney W. D. 1885. The roots, verb forms and primary Derivatives of the Sanskrit language. A supplement to his Sanskrit grammar. Leipzig.