Consonant sandhi within a word

In the previous lesson, we learned that consonant sandhi can occur between two different words:

  • तत् इच्छामि → तद् इच्छामि।
    tat icchāmi → tad icchāmi.
    I want that.

Consonant sandhi also occurs within a single word:

  • मरुत् + भिः → मरुद्भिः
    marut + bhiḥ → marudbhiḥ
    by the winds

Consonant sandhi within a word is complex and complicated. In this lesson, we will explain some of its general patterns.

General changes

If the second sound is a vowel, nasal sound, or semivowel, there are usually no sandhi changes:

  • वच् + अन्ति → वचन्ति
    vac + anti → vacanti

  • वच् + मि → वच्मि
    vac + mi → vacmi

  • वाच् + य → वाच्य
    vāc + ya → vācya

Otherwise, consonant sandhi within a word generally the same principles we learned about in the previous lesson.

Preserving aspirated sounds

One important difference is that we should preserve aspirated sounds if possible. This idea is difficult to explain, but it is easy to understand:

  • बुध् + त → बुद्ध
    budh + ta → buddha
    (aspiration moves to ta)

  • लभ् + त → लब्ध
    labh + ta → labdha
    (aspiration moves to ta)

  • बोध् + स्य → भोत्स्य
    bodh + sya → bhotsya
    (aspiration moves to the first consonant)

  • दह् + स्य → धक्ष्य
    dah + sya → dhakṣya

  • दह् → धक्
    dah → dhak
    (aspiration moves to the first consonant)

But sometimes, there is no sound we can move the aspiration to. In these instances, we remove the aspiration completely:

  • मुह् → मोक्ष्यति
    muh → mokṣyati
    be deluded → will be deluded

  • मुह् → मुक्
    muh → muk
    (m stays the same.)


In Sanskrit, n often shifts its point of pronunciation and becomes :

  • गुरुना → गुरुणा
    gurunā → guruṇā

  • विषेन → विषे
    viṣena → viṣeṇa

Generally, the sounds r and change n to . This change can occur even if the two sounds are separated by other sounds:

  • रामेन → रामे
    rāmena → rāmeṇa

  • रामायन → रामाय
    rāmāyana → rāmāyaṇa

  • वर्षभोग्येन → वर्षभोग्ये
    varṣabhogyena → varṣabhogyeṇa

Which sounds can come in between? Generally, any sound that we can pronounce without moving our tongue very much can come in between. These sounds include:

  • all vowels

  • y and v

  • consonants pronounced with the soft palate (k kh g gh ṅ h)

  • consonants pronounced with the lips (p ph b bh m)

There are many exceptions and subtleties to this rule. For now, just remember that n often changes to if it follows r or .


Likewise, s often shifts and becomes :

  • अग्नि + सु → अग्निषु
    agni + su → agniṣu

  • धनुस् + आ → धनुषा
    dhanus + ā → dhanuṣā

Generally, any vowel other than a or ā changes the following s to . The consonant k can cause this change too:

  • वाक् + सु → वाक्षु
    vāk + su → vākṣu

In English, this change is sometimes called the ruki rule because it is caused by “r” sounds (ṛ ṝ), “u” sounds (u ū o au), “k” sounds (k), and “i” sounds (i ī e ai).

There are many exceptions and subtleties to this rule. For now, just remember that s often changes to if it follows “ruki” sounds.