Conjunct consonants are a type of letters, used for example in Brahmi or Brahmi derived modern scripts such as Balinese, Bengali, Devanagari, Gujarati, Tibetan, Dzongkha etc to write consonant clusters such as /pr/ or /rv/.
In modern Devanagari the components of a conjunct are written left to right when possible (when the first consonant has a vertical stem that can be removed at the right), whereas in Brahmi characters are joined vertically downwards.
[1] Some simple examples of conjunct consonants in Devanagari are: त + व = त्व (tva), ण + ढ = ण्ढ (ṇḍha), स + थ = स्थ (stha), where the vertical stroke of the first letter is simply lost in the combination.
Some examples of conjunct consonants in Gujarati are: પ + ઝ = પ્ઝ (pjha) (where a stroke of the first letter is lost in the combination), હ + ળ = હ્ળ (hḷa), જ + ભ = જ્ભ (jbha).
[2] In Balinese, conjunct consonants are called Haksara Wrehastra.