Definition: Not having any force or weight applied to it; free from stress or tension.

Example: The pressureless environment allowed the experiment to proceed without any external influences.

Definition: Relating to the time or activities that occur before a surgical operation.

Example: The doctor explained the presurgery procedures to ensure I was well-prepared.

Definition: Referring to the period before symptoms of a disease appear, making it difficult to diagnose accurately.

Example: The presymptomatic phase of the illness can last for several days, during which the person may not feel unwell.

Definition: Referring to the part of a nerve cell that sends signals to another cell at a synapse, occurring before the signal is transmitted.

Example: The presynaptic neuron releases neurotransmitters into the synaptic cleft.

Definition: In a way that relates to the presynaptic part of a neuron, which is the area before a synapse where signals are transmitted.

Example: The neurotransmitter is released presynaptically to communicate with the next neuron.

Definition: Happening or being born before the usual or expected time, especially in relation to pregnancy.

Example: The hospital has a special unit for caring for preterm infants.

Definition: A baby that is born before the usual time, specifically before 37 weeks of pregnancy have passed.

Example: The hospital has a special unit for caring for preterm infants.

Definition: To apply a treatment to something before it is used or processed further.

Example: Before painting, you should pretreat the wood to ensure better adhesion of the paint.

Definition: A process or treatment that is done before another treatment or procedure.

Example: The water undergoes a pretreatment to remove impurities before it is purified.

Definition: The total number of cases of a particular condition or disease in a specific population at a certain time.

Example: The prevalence of diabetes has increased in recent years.

Definition: To stop something from happening or to make it impossible.

Example: Nothing can prevent us from achieving our goals.

Definition: To stop something from happening or to keep someone from doing something.

Example: The new law was designed to prevent accidents on the road.