/espeɾanˈtista/
Esperantic, Esperantist
“2013, F Millán Romeral and T Brandsma, "El poema del P. Tito Brandsma en esperanto e interlingua", Ordinis Carmelitarum, Vol. 63 N. 1” — Because of all this, it is more than understandable that the "Esperantist world" would look back with admiration on the figure of P. Tito.
esperantista is masculine or feminine depending on context in Spanish.
Esperantist (supporter or speaker of Esperanto)
“Sabemos por Manuel Casanoves que fue esperantista y miembro de la IKUE (Internacia Katolika Unuigo Esperantista). We know through Manuel Casanoves that he was an Esperantist and member of the IKUE (Internacia Katolika Unuigo Esperantista).”