Borrowed from Arabic شَكَا (šakā, “to complain”) or more likely a derivative. The -ch- points to Maghrebi Arabic tšakka, from classical تَشَكَّى (tašakkā), which is a frequentative/intensive of the first-mentioned verb. Alternatively it might perhaps be from the noun الشَكْوَى (aš-šakwā, “complaint”); compare achaque.

• IPA^(key): /at͡ʃaˈkaɾ/ [a.t͡ʃaˈkaɾ]
• Rhymes: -aɾ
• Syllabification: a‧cha‧car

achacar (first-person singular present achaco, first-person singular preterite achaqué, past participle achacado)

1. to attribute (something to someone); to blame

   Synonyms: culpar, echar la culpa, responsabilizar, imputar, atribuir

   • 1999 October 21, Amelia Castilla, “Mañas completa con 'Sonko 95' su tetralogía sobre jóvenes de los 90”, in El País‎^[1], Madrid, →ISSN:

     […] A esa característica de su literatura achaca Mañas el gancho que tienen sus novelas para ser adaptadas al cine.

     (please add an English translation of this quotation)

• “achacar”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8.1, Royal Spanish Academy [Spanish: Real Academia Española], 15 December 2025