Used to describe involuntary responses to stimuli, not deliberate actions.

Physical Reaction

Highlights an instantaneous response to conditions like temperature or emotion.

Immediate Effect

Reflects formal agreements, typically used in professional or business environments.

Suggests a deliberate choice to bring in resources or personnel for a specific purpose.

Conveys the unintended nature of becoming ill or catching a disease.

Used in medical or health-related contexts, often with a sense of caution.