This is where the -u in babhru seems to come from.
pukar tawny colour, brown; spot (Pur-ana_.3); fault, defect, blemish
(Tol. Er..ut. 369); tawny-coloured bull or cow (Kalit. 105); pogaru
tawny colour (Te.); pukar id. (Ma.)(Ta.lex.) pogar shine,
brightness, lustre, colour (Ka.)(DEDR 4232). pur-ku tawny colour,
dimness (Ta.lex.) po_r-k-ka_l.ai bullock with spots on the body;
po_r tawny colour; spot; pukar colour (Pat.t.in-ap. 74); brightness,
light; pukar beauty (Cilap. 9,10); pukavu mounting, as a vehicle
(Paripa_. 10,14)(Ta.lex.) buro (of horse or cow) whitish (Sh.); bura
coarse white sugar (K.); bhu_ro brownish, whitish (S.); white, fair
(Ku.); bhu_ra_ brown (L.P.H.); brown sugar (Bi.); bhuro brown (N.);
bhura_ brown sugar (B.Or.); light brown (M.); bhu_ru~ brown, white
(G.); bhurra_ black and white pigeon (N.); bhu_rra_ brown sugar
(Bi.); bhulla light brown (Mth.); bhurka_ dirty white (M.)(CDIAL
9690). pul tawny colour; pullai yellowish colour (Ta.); pulla a
yellowish colour of cattle (Ma.); pula light brown colour (Ga.);
yellowish (Te.)(DEDR 4310). pu_shkun yellow (Br.)(DEDR 4356). pu_cal
brownish colour (Ta.lex.) Venus: pukar, pukaro_n- Venus (Ta.);
bhr.gu (Skt.)(Ta.lex.)
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