Arabic

labān- - chest, especially the part between the teats, chest (of any hoofed animal); breast (BK 2 962, WKAS II 169)

PS
*labb(-at)-, *lab(y)-ān- - (animal's) body from neck to rump (SED I No. 173)

Meaning somewhat diffuse (originally may denote trunk as a whole). Semantically and phonetically (­a­ vs. ­i­) rather to be separated from *libb-­ ‘heart’.