1) Monosaccharide 2) Monosaccharose 3) Simple sugar 
A pentose is a monosaccharide with five carbon atoms. Pentoses are organized into two groups. Aldopentoses have an aldehyde functional group at position 1. Ketopentoses have a ketone functional group in position 2 or 3. ==Aldopentoses== The aldopentoses have three chiral centers and therefore eight different (2^3) stereoisomers are possible. ==Ket...
• (n.) Any of a group of sugars of the formula C5H10O5, as arabinose; -- so called from the five carbon atoms in the molecule. They are not fermented by yeast.
A monosaccharide (simple sugar) containing five carbon atoms in the molecule. Examples include is ribose and deoxyribose which are important consituents of the nucleic acids RNA and DNA, respectively. Pentoses also make up various plant polysaccharides, such as pectin and gum arabic.
<chemistry> Sugar (monosaccharide) with five carbon atoms. Include ribose and deoxyribose of nucleic acids and many others such as the aldoses arabinose and xylose and the ketoses ribulose and xylulose. ... (12 Dec 1998) ... 
(pen´tōs) a monosaccharide containing five carbon atoms in a molecule.
Pen'tose noun [ Penta- + - ose .] (Chemistry) Any of a group of sugars of the formula C 5 H 10 O 5 , as arabinose; -- so called from the five carbon atoms in the molecule. They are not fermented by yeast. 
Type: Term Pronunciation: pen′tōs Definitions: 1. A monosaccharide containing five carbon atoms in the molecule; arabinose, lyxose, ribose, xylose, xylulose.
A pentose is a sugar with five carbon atoms in the molecule.
[n] - any monosaccharide sugar containing five atoms of carbon per molecule
pentose A monosaccharide containing five carbon atoms in a molecule.
noun any monosaccharide sugar containing five atoms of carbon per molecule