Unipolär

Unipolär (from Latin uni- "one" + polar "pole") is an adjective used in several fields to indicate a single pole, polarity, or dominant element. It appears in technical, medical and geopolitical contexts with distinct meanings.

In electronics and electrical engineering, unipolär describes devices or signaling that rely on one type of electric charge or a single polarity. Examples include unipolar transistors (field-effect devices that operate with majority carriers), unipolar stepper motors (with center-tapped coils driven so each phase uses a single polarity relative to a common return), and unipolar signaling schemes. In electrophysiology, unipolar recordings use one active electrode referenced to a distant or combined reference, as in some ECG leads.

In psychiatry, unipolär refers to mood disorders characterized solely by depressive episodes without manic or hypomanic episodes; the term is often used in contrast to bipolar disorder. It is commonly associated with major depressive disorder in diagnostic contexts, though modern classifications emphasize specific diagnostic criteria.

In geopolitics, unipolär describes an international system dominated by a single superpower, commonly used to analyze post–Cold War global order.

The term is cross-disciplinary and context-dependent; its precise meaning is clarified by the domain in which it is used.