Smite

Smite is a category of unique weapon attacks which, unlike normal attacks which cost an Action, expend Spell Slots (often additionally a Bonus action) in order to activate. As they are considered weapon attacks they can be used with and trigger  Extra Attack, and in the case of  Divine Smite can be used multiple times per combat turn.

List of Smite abilities

•  Divine Smite
•  Banishing Smite 
•  Blinding Smite
•  Searing Smite 
•  Thunderous Smite
•  Wrathful Smite 

Except for Divine Smite, all of the other smites function the same. Here are the key differences between Divine Smite and the other smites.

Divine Smite

Despite consuming spell slots, Divine Smite is not a spell and does not interact with any effect or ability that only works with spells. Examples include  Counterspell, Vivacious Cloak, or  Tempestuous Magic. Other smites, such as  Thunderous Smite, are proper spells and will interact with these effects.

• Divine Smite cannot be triggered by ranged attacks.
• Does not consume the spell slot on a miss.
• Deals Weapon Damage +
  • 2d8RadiantDRS (to normal enemies)
  • 3d8RadiantDRS (to fiends and undead)
    • If the weapon attack roll is a critical hit, the damage is doubled (4d8Radiant, increasing by 2d8Radiant for each spell slot level above 1st).

Unlike other smite spells, Divine Smite can also be configured to trigger automatically on a hit or critical hit via the reactions menu. See  Divine Smite (reaction). This allows you to use Divine Smite on any melee weapon attack and multiple times per turn, even while dual-wielding. When triggered in this way, the only additional resource consumed is the selected level of spell slot.

• Despite being configured in the Reactions menu, Divine Smite never consumes the Reaction resource.
• Divine Smite can be triggered as a reaction when using other smites, allowing for two different smites in a single attack.

Other Smites

Other smites cannot be triggered as reactions and must be used manually; however, Divine Smite can be triggered as a reaction when using other smite spells allowing for two different smites in a single attack. They also count as a spell for the purposes of features like  Tempestuous Magic or  Empowered Evocation.