first model
first models
first module
first molars
first moment
first month
first mutation
first myocardial infarction
first name
first night
first objective
first observation

first occasion
first occurrence
first onset
first operation
first opportunity
first option
first order
first order elimination
first order kinetics
first order phase transitions
first order reaction
first outbreak
first outlines

first ovulation
first oxidation
first pair
first paper
first parameter
first part
first pass
first passage times
first patient
first pattern
first peak
first period
first permanent molars

first person
first phase
first physician
first place
first point
first polar body
first population
first position
first post-operative week
first postnatal month
first postnatal week
first postoperative day
first postoperative week

first postoperative year
first prediction
first pregnancy
first premolar
first prenatal visit
first preparation
first prescription
first present