Clauson (1972)
An etimological dictionary of pre-thirteenth-century Turkish
p. 294
D bıçığ
Dev. N. fr. biç-; ‘an agreement’; the semantic connection is not obvious, but the derivation is certain, cf. bıçğa:s. Survives only(?) in NE Tel. pıçu:; SC biçik ‘the cut of a garment’ R IV 1318. Xak. xi bıçığ (misvocalized baçığ) al-mīṯāq wa’l-‘ahd ‘contract, agreement’; hence one says ol meniŋ birle: bıçığ (sic) kıldı: ‘āhada ma‘ī ‘he made an agreement with me’ Kaş. I 371: xiii(?) Tef. bıçığ translates al-‘ahd and bıçığ kıl- ‘ahida 93 (unvocalized; Borovkov, misled by the main entry in Kaş., transcribed as baçığ).