华彩乐段（Cadenza[s]）指独奏部分的装饰性乐段，既可以预先创作亦可以即兴表演，形式自由，并时常有炫技意味。此乐段以所有声部的延音作标记，并常常出现在乐曲的尾声前。

在协奏曲中华彩乐段的部分，其他乐器静止，独奏者则以自由拍子表演。有时候作曲家同时提供自己的华彩乐段版本，一些更会加入小部分其他乐器的伴奏，如拉赫玛尼诺夫第3钢琴协奏曲中钢琴在弹奏琶音时长笛、单簧管和法国号分别加入。华彩乐段常常出现在首乐段的尾声前，但有少数例外如柴可夫斯基第1钢琴协奏曲中它出现在第一乐段首五分钟。

In music, a cadenza (from Italian:cadenza [kaˈdɛntsa], meaning cadence; plural, cadenze [kaˈdɛntse]) is, generically, an improvised or written-out ornamental passage played or sung by a soloist or soloists, usually in a "free" rhythmic style, and often allowing for virtuosic display. Indicated by a fermata in all parts if improvised, a cadenza is usually over a final or penultimate note in a piece or important cadence and the accompaniment rests or sustains a note or chord. Thus it is often before a final coda or ritornello.