(US, telephony) An audible signal to the calling party that indicates failure to complete the requested connection; an engaged tone

plural of virtue signaler

Alternative spelling of virtue signaller

to share or disseminate another's information or material with one's own audience

an instance of sharing or disseminating another's information or material with one's own audience / (engineering) an increase in the capacity, strength, or range of a signal

An event or emanation to which a sensing device gives an undesired positive response.

plural of signal box

A building, typically adjacent to or spanning a railway line, from where signals, points and (sometimes) level crossings are controlled. / The alarm-box of a police or fire-alarm system.

(biochemistry) A series of chemical reactions within a cell which start when a transmembrane protein comes into contact with a chemical signal, resulting in a second messenger being triggered.

(endocrinology) A type of cell signaling involving the release of a hormone from a nerve cell that has an effect on another cell.