Final answer:
The waxy coating that minimizes water loss in plants is a type of lipid, composed of waxes formed by long-chain fatty acids and long-chain alcohols.
Step-by-step explanation:
The waxy coating that reduces water loss from plants by being impermeable to water is a type of lipid. Lipids are diverse compounds that are insoluble in water due to their hydrophobic nature. Specifically, the waxy cuticle on plant surfaces is composed of long-chain fatty acids that are esterified to long-chain alcohols, forming waxes. This coating minimizes water loss through transpiration and provides a barrier to protect the plant from dehydration and external harms.