5e SRD >Spells >

Shield

1st-level abjuration

Casting Time: 1 reaction, which you take when you are hit by an attack or targeted by the magic missile spell
Range:Self
Components:V, S
Duration:1 round

An invisible barrier of magical force appears and protects you. Until the start of your next turn, you have a +5 bonus to AC, including against the triggering attack, and you take no damage from magic missile.