Proto-Basque: *sil
Meaning: 1 navel, umbilical cord 2 abdomen, paunch 3 penis 4 plumule (of a seed)
Bizkaian: ziil, zil 1, 4, zil-bor 2, zil-bot 2, (Oñate) txil-bor 2
Gipuzkoan: ziil 1, txil-ko 1, txil-bor 1, zil-bor 2, (Andoain) zil 3
High Navarrese: txil-ko 1, txil-bur 1
Low Navarrese: (Aldude, Garazi) xil-ko 1, (Amikuse) xil-khoi 1
Lapurdian: xil-ko 1
Baztanese: xil-ko 1
Comments: Several forms exhibit expressive palatalization of the initial /č/, /š/ and the diminutive suffix *-ko. Some other Bsq words meaning 'paunch' or 'tallow' (gilbor, bilgor, bilkor) are unrelated, but apparently have contaminated with zilbor, txilbor, etc. Bengtson (Dhumbadji! 4.1, 1998) proposed a comparison of Bsq *sil with Tabasaran c̣ul 'navel' and Dargi č̣ilič̣a id., but it is problematic.
