early 12c., "to strive toward, devote oneself to, cultivate" (translating Latin occupatur), from Old French estudiier "to study, apply oneself, show zeal for; examine" (13c., Modern French étudier), from Medieval Latin studiare, from Latin studium "study, application," originally "eagerness," from studere "to be diligent," from PIE *(s)teu- (1) "to push, stick, knock, beat" (see steep (adj.)). The notion appears to be "pressing forward, thrusting toward," hence "strive after."
Martha swanc and becarcade to geforðigene þan Hælende and his þeowen þa lichamlice behefðen. Seo studdede emb þa uterlice þing. [Homily for the Feast of the Virgin Mary, c.1125]
From c. 1300 as "apply oneself to the acquisition of learning, pursue a formal course of study," also "read a book or writings intently or meditatively." From mid-14c. as "reflect, muse, think, ponder." Meaning "regard attentively" is from 1660s. Related: Studied; studying.
late 14c., from Old French estudiant "student, scholar, one who is studying" (Modern French étudiant), noun use of past participle of estudiier, from Medieval Latin studiare "to study," from Latin studium (see study (v.)). An Old English word for it was leorningcild "student, disciple."
Student-teacher in reference to a teacher in training working in a classroom under the supervision of a head teacher is from 1851, American English (pupil-teacher in the same sense is by 1838).