Master the core vocabulary of child health, from newborn care to common childhood illnesses, with precise definitions.
Last updated: October 12, 2026
Pediatrics is the branch of medicine devoted to infants, children and adolescents. This page defines the key terms used in newborn care, growth and development, vaccination and common childhood conditions, so you can read charts and clinical notes with confidence.
| Term | Definition |
|---|---|
| Neonate | A newborn infant in the earliest period after birth, when adaptation to life outside the womb is most critical. |
| Infant | A very young child in the first stage of life, who depends entirely on caregivers for feeding and protection. |
| Adolescent | A young person in the transition between childhood and adulthood, marked by puberty and rapid physical and emotional change. |
| Prematurity | Birth that occurs before the pregnancy has reached full term, often requiring specialized neonatal care. |
| Apgar score | A quick assessment of a newborn's condition after birth, based on appearance, pulse, reflexes, activity and breathing. |
| Fontanelle | A soft, membrane-covered gap between the skull bones of an infant that allows the head to grow and later closes. |
| Growth chart | A graph that compares a child's weight, length or height and head circumference with reference patterns for age and sex. |
| Developmental milestone | A skill that most children acquire at a typical stage, such as smiling, sitting, walking or speaking. |
| Primitive reflex | An automatic response present in newborns, such as sucking or grasping, that fades as the nervous system matures. |
| Immunization | The process of protecting a child against infectious diseases by administering vaccines. |
| Well-child visit | A routine preventive appointment to monitor growth, development, vaccination status and family concerns. |
| Breastfeeding | Feeding an infant with human milk directly from the breast. |
| Colic | Episodes of prolonged, unexplained crying in an otherwise healthy infant, usually with apparent abdominal discomfort. |
| Jaundice | A yellowish discoloration of the skin and eyes caused by excess bilirubin, frequently seen in newborns. |
| Bronchiolitis | A viral infection of the small airways of the lungs in infants, causing cough, wheezing and labored breathing. |
| Croup | A viral infection of the upper airway causing a barking cough, hoarse voice and noisy breathing in young children. |
| Otitis media | Inflammation or infection of the middle ear, a common cause of ear pain and fever in children. |
| Febrile seizure | A convulsion triggered by a rapid rise in body temperature in a young child, without underlying brain infection. |
| Gastroenteritis | Inflammation of the stomach and intestines causing vomiting and diarrhea, with a risk of dehydration in children. |
| Dehydration | A state in which the body lacks sufficient fluid, which can develop quickly in small children. |
| Atopic dermatitis | A chronic inflammatory skin condition causing dry, itchy patches, often beginning in early childhood. |
| Asthma | A chronic inflammatory disease of the airways causing recurrent wheezing, cough and breathlessness. |
| Failure to thrive | Inadequate weight gain and growth in an infant or child compared with expected patterns. |
| Congenital anomaly | A structural or functional abnormality present at birth. |
| Pediatrician | A physician who specializes in the medical care of infants, children and adolescents. |
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Start learning free →Pediatric vocabulary lets students, nurses and medical assistants read records, understand growth and development assessments, communicate precisely with families and colleagues, and document the care of infants, children and adolescents accurately.
Yes. This vocabulary is core to US health programs — nursing school and NCLEX prep, pre-med, and medical assistant training. MediLearn lets you drill these terms with quizzes and flashcards using spaced repetition.
Birth that occurs before the pregnancy has reached full term, often requiring specialized neonatal care.
Episodes of prolonged, unexplained crying in an otherwise healthy infant, usually with apparent abdominal discomfort.
A chronic inflammatory skin condition causing dry, itchy patches, often beginning in early childhood.