Irregular warfare is warfare employing the tactics commonly used by irregular military organizations. Organic forms are typically irregular and asymmetrical. It is characterized as an irregular waveform. Sweating, shortness of breath, lightheadedness, and irregular heartbeat may also be experienced. An implantable cardiac defibrillator may be recommended in those with certain types of irregular heartbeat. Estrogen also reduces the incidence of irregular breakthrough bleeding. Each is irregular and quadrilateral in shape. There are many nouns with irregular plurals. Additive meters have a pattern of beats that subdivide into smaller, irregular groups. A higher occurrence is reported in people with irregular sleep schedules. They are commonly divided into spiral, elliptical and Irregular galaxies. Some people with diverticulosis complain of symptoms such as cramping, bloating, flatulence, and irregular defecation. Jupiter trojans are dark bodies of irregular shape. Galaxies are categorized according to their visual morphology as elliptical, spiral, or irregular. The meaning refers more specifically to combinations of words with irregular rhythms.