subdwarf
/ˈsʌbdwɔːf/noun
1A tree, especially a cultivar, that is smaller than a size regarded as dwarf. Compare dwarf. rare.
2 Astronomy. A star which lies just below the main sequence on the Hertzsprung–Russell diagram, being less luminous than main sequence stars of the same temperature or spectral type.
Origin
Early 20th century; earliest use found in Bulletin Natal Department Agriculture. From sub- + dwarf.