From Middle English heedstrong, equivalent to head + strong.

headstrong

1. Determined to do as one pleases, and not as others want.

   He was in that headstrong teenage phase when he felt like he knew everything.

   • 1775 January 17 (first performance), [Richard Brinsley Sheridan], The Rivals, a Comedy. […], London: […] John Wilkie, […], published 1775, →OCLC ↗, Act III, scene iii, page 52 ↗:

     O, there's nothing to be hoped for from her! ſhe's as headſtrong as an allegory on the banks of the Nile.

• See also Thesaurus:obstinate

• French: obstiné
• German: eigensinnig
• Italian: determinato
• Portuguese: obstinado
• Russian: своенравный
• Spanish: díscolo, desconsiderado