signálem

Signálem is the instrumental singular form of the Czech noun signál, meaning "signal." It functions as a grammatical inflection rather than a separate lexical item, and is used to express means or the instrument by which an action is performed, typically after verbs of signaling, controlling, or reacting. For example, "Systém reaguje signálem" (The system responds by a signal). The noun signál has senses including a physical signal (electrical or radio), a traffic signal, or any indicator conveying information. The form signálem follows standard masculine inanimate instrumental singular declension in Czech.

In Slovak, the corresponding instrumental singular is signálom, reflecting language-specific declension. In Czech dictionaries, signálem is presented as the instrumental form of signál rather than as a separate entry.

Because signálem is a grammatical form rather than a standalone lexical item, its use is dictated by Czech syntax and morphology. It is primarily encountered in written and spoken Czech when describing the means by which an action is performed. See also signál, and related terms in signaling and communication.