Modifier

Modifiers are suffixes attached to incantations to alter the effects of a spell, for example, to increase its strength.

Numerical
The numerical modifiers are Duo and Tria. When each is attached to a spell's inantation they increase its strength and can potentially change the spell's appearance, Tria more so than Duo.

Maxima
the Maxima modifier greatly increases the strength of a spell, possibly to its highest intensity, such as the Wand-Lighting Spell, the Shield Charm and Bombarda.

Solem
This modifier was only ever used with Lumos, which converted its harmless, all-round glow into a harsh ray of light.

Evanesco
The Vanishing Spell is performed by attaching the modifier "evanesco" to the name of the object you wish to vanish. It is unknown if this spell would work if no object was verbally specified.

Behind the scenes

 * Although modifiers have appeared many times in the games and films of the franchise, they have never appeared in the books.