Relevancia vs. pertinencia
While both relevancia and pertinencia can be translated to English as "relevance", they focus on entirely different concepts. The word relevancia refers to the importance, magnitude, or significance of something. On the other hand, the word pertinencia refers to how appropriate, applicable, or connected something is to a specific situation or topic.
Relevancia
The word relevancia is used to express the importance, significance, or prominence of a subject, event, or person. It implies that something matters deeply, has a major impact, or stands out as highly significant in a broad sense.
El descubrimiento científico tiene gran relevancia para la medicina moderna.
(The scientific discovery has great relevance for modern medicine.)
La relevancia de este autor en la literatura contemporánea es innegable.
(The relevance of this author in contemporary literature is undeniable.)
Los expertos debatieron sobre la relevancia de adoptar nuevos hábitos alimenticios.
(The experts debated the relevance of adopting new eating habits.)
El periódico dedicó su portada a un evento de interés y relevancia internacional.
(The newspaper dedicated its front page to an event of international interest and relevance.)
El profesor destacó la relevancia histórica del tratado de paz.
(The professor highlighted the historical relevance of the peace treaty.)
Pertinencia
The word pertinencia is used to describe how appropriate, suitable, or applicable something is to the specific context being discussed. It evaluates whether a comment, argument, or action belongs in the current situation, regardless of its overall importance.
El juez cuestionó la pertinencia de la evidencia presentada por la defensa.
(The judge questioned the relevance of the evidence presented by the defense.)
Dudo de la pertinencia de tus chistes durante una reunión de negocios tan seria.
(I doubt the relevance of your jokes during such a serious business meeting.)
El comité evaluó la pertinencia del curso de diseño para los estudiantes de ingeniería.
(The committee evaluated the relevance of the design course for the engineering students.)
Tus preguntas perdieron pertinencia cuando el tema de debate cambió radicalmente.
(Your questions lost relevance when the debate topic changed radically.)
La directora confirmó la pertinencia de aplicar las nuevas normas de seguridad.
(The director confirmed the relevance of applying the new safety rules.)
Summary
To summarize, choose relevancia when you want to highlight the importance, weight, or significance of something. Choose pertinencia when you need to express that something is fitting, applicable, and on-topic for a specific scenario. A fact can hold massive relevancia globally, but have absolutely no pertinencia to the specific conversation you are having right now.