Talla vs. tamaño
In Spanish, both 'talla' and 'tamaño' can be used to refer to 'size'. However, the usage of these words varies in different contexts.
Talla
'Talla' is generally used to express size when discussing clothing or footwear, as well as stature (in terms of a person's height) and diamond size.
Esta camisa es de mi talla.
(This shirt is my size.)
La talla de estos zapatos es 38.
(The size of these shoes is 38.)
Ella tiene una talla baja.
(She has a short stature.)
La talla del diamante es impresionante.
(The size of the diamond is impressive.)
Tamaño
'Tamaño', on the other hand, is more frequently used when referring to the dimensions or proportions of objects, animals, shapes or structures. It could also refer to the degree or extent of a situation.
El tamaño de este coche es perfecto para mí.
(The size of this car is perfect for me.)
Su perro es de tamaño mediano.
(Her dog is medium-sized.)
Estoy sorprendido por el tamaño del problema.
(I am surprised at the extent of the problem.)
El tamaño de esta pizza no es suficiente para cuatro personas.
(The size of this pizza is not enough for four people.)
Summary
'Talla' and 'tamaño' are two Spanish words often used interchangeably to denote 'size'. However, it's important to remember that 'talla' commonly depicts clothing sizes, stature or certain specific sizes such as those of diamonds. Meanwhile, 'tamaño' covers a wider range - it denotes dimensions or proportions in general and goes beyond physical extents to reflect figurative scopes as well.