Definir means 'to define', and it is a regular -ir verb useful for explanation and analysis. ¿Cómo defines el éxito? (how do you define success?), es difícil de definir (it's hard to define). Because defining terms and concepts is part of structured, higher-level writing, definir adds useful range to essays. The reflexive definirse can mean to take a clear position. As a regular -ir verb the conjugation is predictable, and the related adjective definido ('defined') and noun la definición are easy to learn alongside it.
Quick facts
Definir (to define) is a regular -ir verb.
Real sentences across different tenses — the kind of thing you'd actually say or write.
¿Cómo defines el éxito? (how do you define success?).
Useful for explaining concepts in essays.
Reflexive definirse (to take a clear position).
La definición, definido.
Fixed expressions worth knowing — they come up in listening, reading and writing tasks.
Idiomatic expressions
definir is a regular -ir verb — it follows the standard -ir pattern in every tense. That makes it a good one to drill: if you know definir, you know the template for all regular -ir verbs.
Type conjugations from memory and get instant feedback. That's how you actually build the automatic recall the exam needs — not from reading tables.
Practice definir now →Three questions, no account needed. Type the form, then press Enter or tap Check.
yo: defino, tú: defines, él: define, nosotros: definimos, vosotros: definís, ellos: definen
The past participle is definido (he definido) and the gerund is definiendo (estoy definiendo).
Definir is on the Eduqas GCSE Spanish vocabulary list, but not on AQA or Edexcel.
Verbs that are easy to confuse with definir or that behave like it.
Definir is on the Eduqas GCSE Spanish vocabulary list, but not on AQA or Edexcel. Compare the exam boards.
Written by Daniel Holmes for GCSE & A-Level Spanish students.