PIE base ‘to stick, adhere; fat’.
Other derivatives include live, leave, delay, liver ‘organ for digestion of fats’, lipo- ‘relating to fat or other lipids’, from Greek lipos ‘fat’, and aliphatic (compound), like methane, ethane, and propane, from Greek aleiphein ‘to anoint with oil’.
[Pokorny *leip-1 ‘smear (with fat), stick’, pp. 670–671.]