Silence
Silence is a detrimental status effect which prevents the use of Spells. Pacification and Amnesia are equivalents that disable the use of Weaponskills and Abilities, respectively. In PvP, this status effect will stop the use of all abilities.
Note that Silence is relevant not just for mages, but also for jobs that use both Weaponskills and Spells - for example,
Dark Knight's AoE combo actions ( Unleash and Stalwart Soul) are both Spells, but most of their other actions are Weaponskills - meaning that Silence can hinder a Dark Knight's AoE damage and enmity management against groups of enemies.
History
All PvE player actions that caused Silence were changed as of Shadowbringers (5.0) to no longer cause the status. For the effect that replaced the players' use of Silence, see Interrupt.