oral phase; oral stage
In Freudian psychoanalysis, the first psychosexual stage (birth to about 18 months) where pleasure centers on the mouth.
According to Freud, fixation at the oral stage influences later personality.
The phallic stage, the third psychosexual stage, following the anal stage.
From 口唇 (こうしん, 'lips; mouth') + 期 (き, 'period; stage'), a calque of the English 'oral stage' used in Freudian psychoanalysis.