Which time signature is an example of Irregular metre?

The time signature of 5/4 is an example of irregular metre because it does not conform to the more common patterns of regular time signatures, which typically divide the beats into equal groupings, such as 2/4, 3/4, or 4/4. In regular metres, the beats are easily quantifiable and follow a predictable pattern.

In contrast, 5/4 features five beats in a measure, which can create a sense of asymmetry. This makes it less predictable and more complex in its rhythmic structure. Composers often utilize irregular metre to create a unique musical effect or to convey a particular emotional or narrative quality that cannot be achieved with more standard time signatures.

Regular metres like 3/4, 4/4, and 6/8 have a strong feeling of pulse that is easier for listeners to follow, while 5/4's uneven grouping can lead to a more fluid and contrasting musical experience. As a result, it is categorized as irregular because of its distinctive feel compared to standard metres.