Wiktionary
n. (cx neologism English) Warfare that blends conventional warfare and irregular warfare (potentially including cyberwarfare and information warfare) — the full spectrum of conflict.
Wikipedia
Hybrid warfare is a military strategy that blends conventional warfare, irregular warfare and cyberwarfare. By combining kinetic operations with subversive efforts, the aggressor intends to avoid attribution or retribution. Hybrid warfare can be used to describe the flexible and complex dynamics of the battlespace requiring a highly adaptable and resilient response. There are a variety of terms used to refer to the hybrid war concept: hybrid war, hybrid warfare, hybrid threat, or hybrid adversary. US military bodies tend to speak in terms of a hybrid threat, while academic literature speaks of a hybrid warfare. For the purposes of this article, these terms are used interchangeably.