a research student (i.e. a visiting or non-matriculating graduate student) / a researcher

researcher

a laboratory

researcher

research association; research society / group of enthusiasts (as may be found in schools, colleges, etc)

research & development; R&D

(education) research project, done by Japanese schoolchildren during summer break, to be presented upon return to school

(mathematics) inverse function

(trigonometry) a trigonometric function

(calculus) derived function - of a function, another function, the value of which for any value of the independent variable is the instantaneous rate of change of the given function at that value of the independent variable.