"Outright lying" means lying, as opposed to simply exaggerating, omitting relevant information, or otherwise "bending" the truth.

You use outright to describe behaviour and actions that are open and direct, rather than indirect. Kawaguchi finally resorted to an outright lie. 川口最后干脆睁着眼睛说瞎话。 She could not tell him an outright lie. 她无法对他彻头彻尾地撒谎。