#embryology

• ab origine - A Latin phrase meaning 'from the origin' or 'from the very beginning'. In medical genetics and embryology, it is used to describe a chromosomal anomaly, congenital malformation, or metabolic disorder present in the organism's biological framework since the moment of conception (ab origine), as opposed to conditions acquired later in life.
• ab ovo - A Latin phrase derived from Horace's writings, meaning literally 'from the egg'. In embryology and developmental toxicology, it refers to analyzing a biological process, cellular mechanism, or the action of a teratogenic agent (malformation-inducing toxin) traced right from the egg-cell (zygote) stage or from the moment of fertilization to fully map fetal development disruptions.
• abaxial - An anatomical and histological term describing a structure located away from the axis of the body or an organ, facing away from the central axis. In embryology and developmental anatomy, it refers to surfaces or tissues that develop remote from the median axis (e.g., the lower surface of a primitive formation or a foliar structure used in medical botany).