in Freudian psychoanalytic theory, initial psychosexual stage during which the developing infant's main concerns are with oral gratification. The oral phase in the normal infant has a direct bearing on the infant's activities during the first 18 months of life. For the newborn, the mouth is the all-absorbing organ of pleasure. Freud said that through the mouth the infant makes contact with the first object of libido (sexual energy), the mother's breast. Oral needs are also satisfied by thumb-sucking or inserting environmental objects, such as dolls, other toys, or blankets into the mouth. Freud believed the oral phase begins to shift toward the end of an infant's first year to the anal region.