Ajonjolí vs. sésamo
The Spanish words 'ajonjolí' and 'sésamo' both refer to 'sesame (seed)', but their usage varies depending on the region.
Ajonjolí
'Ajonjolí' is the term commonly used in some Latin American countries such as Mexico, Venezuela, and Colombia to refer to sesame seeds.
Las semillas de ajonjolí son ricas en calcio.
(Sesame seeds are rich in calcium.)
Me gusta poner ajonjolí en mi ensalada.
(I like to put sesame seeds on my salad.)
Sésamo
'Sésamo' is more commonly used in Spain and other Latin American countries such as Argentina to refer to sesame seeds.
El aceite de sésamo es muy saludable.
(Sesame oil is very healthy.)
Usamos semillas de sésamo para decorar el pan.
(We use sesame seeds to garnish the bread.)
Summary
'Ajonjolí' and 'sésamo' are regional variations of the term for sesame seeds in Spanish-speaking countries, with 'ajonjolí' being more prevalent in parts of Latin America and 'sésamo' used in Spain and other regions.