Personal cloaking device
A personal cloaking device was a cloaking device small enough to cloak an individual person.

In 2399, Romulan Zhat Vash operatives decloaked and attacked Jean-Luc Picard and Dahj Asha. Later, Laris and Zhaban examined the security feed and it showed Picard was alone. They wondered if the discrepancy was the result of access to a personal cloaking device. ()
Shield technology