Garry's Mod Wiki

Entity:SetVelocity

  Entity:SetVelocity( Vector velocity )

Description

Sets the entity's velocity. For entities with physics, consider using PhysObj:SetVelocity on the PhysObj of the entity.

Actually binds to CBaseEntity::SetBaseVelocity() which sets the entity's velocity due to forces applied by other entities.
If applied to a player, this will actually ADD velocity, not set it. (due to how movement code handles base velocity)

Arguments

1 Vector velocity
The new velocity to set.