- Small Explorer
- small falling objects fishing
- small fatigue theory
- smallflower galinsoga
- smallflower mikania
- small-footprint LiDAR
- small fractional part
- small gain theorem
- small-gain theorem design
- small-grain boundary
- Small Grams Tripod
- small granule cell
- small group
- small heaven center
- small hydropower
- small image
- small Indian civet
- small inductive dimension
- small-injective module
- small interfering RNA
- small interfering RNA，siRNA
- small intestinal bacterial overgrowth
- small intestinal gland
- small intestine
- small intestine and colon transit test