Habituation

Decrease in Neural or Behavioral Responses with repeated presentation of a stimulus

Habituation decrease in behavioral response

Adaptation decrease in sensory receptor or neural response

I hold that habituation and adaptation are synonyms, although habituation tends to be bound with behavior and adaptation with sensory or neural responses.

Desensitization decrease response by gradual repeated exposure to stimulus

Drug Tolerance response decreases so that larger doses are required to achieve the same effect

Tachyphylaxis rapid development of drug tolerance

Decrease in Learned Responses

Extinction repeated presentation of CS without presentation of the US

Forgetting passage of time without presentation of the conditioned or unconditioned stimuli