In New England, there are three species of small, similar-looking sandpipers known collectively as peeps. Least Sandpipers, who are indeed the smallest peeps, tend to outnumber the other two at inland locations. Along the coast, Semipalmated Sandpipers (pictured above) usually outnumber Leasts, and Western Sandpipers are typically a distant third in abundance.
The term palmated means webbed, so, as you would expect, this species has toes connected by partial webbing. I often refer to these birds in short as Semi-sands. The nickname Semi-pals wouldn't differentiate them from Semipalmated Plovers, who can be called Semi-ploves for short.