1) Protein 2) Protein granule in seeds 
Aleurone (from Greek aleuron, flour) is a protein found in protein granules of maturing seeds and tubers. The term also describes one of the two major cell types of the endosperm, the aleurone layer. The aleurone layer is the outermost layer of the endosperm, followed by the inner starchy endosperm. This layer of cells is sometimes referred to as ...
• (n.) An albuminoid substance which occurs in minute grains (`protein granules`) in maturing seeds and tubers; -- supposed to be a modification of protoplasm.
The proteinaceous and fatty material of the outer-most cell layer of the enodsperm of ripe, small grains.
A·leu'rone noun [ Greek ... flour.] (Botany) An albuminoid substance which occurs in minute grains ('protein granules') in maturing seeds and tubers; -- supposed to be a modification of protoplasm. 
[n] - granular protein in outermost layer of endosperm of many seeds or cereal grains
aleurone, aleuron A granular protein found in the endosperm of many seeds or forming the outermost layer in cereal grains. Alteration of Greek aleuron, 'wheat flour'.
noun granular protein in outermost layer of endosperm of many seeds or cereal grains
protein granulesfound in a single layer of cellsin the outermost portion of the endosperm.