Answer:
the accumulation of favorable variations in a population over time
the way an individual's body adjusts to its environment
Step-by-step explanation:
Adaptation in the biological sense could mean the accumulation of favorable variations in a population over time or the way an individual's body adjusts to its environment.
The environment in which organisms grow is always changing and the body of organisms either finds a way to adjust to the changes in order to continue living or fades off from the population.
Hence, natural selection keeps selecting favorable genes that ensure that organisms survive in the environment and over time, favorable genetic variations keeps accumulating in the population.
Physically, organism's body keeps adjusting itself to the changing environmental conditions in order to keep surviving in the environment.