sandhi
Any of a wide variety of phonological processes that occur at morpheme or word boundaries, such as the fusion of sounds across word boundaries and the alteration of sounds due to neighboring sounds or due to the grammatical function of adjacent words.
countable, uncountable
Mixed sandhi has two divisions, viz. when a word ending in a vowel is followed by a word beginning with a consonant, and when a word ending in a consonant is followed by a word beginning with a vowel. Cases of mixed sandhi are very few, and in the second division are limited to the changes of anusvâra before a vowel.
Where it comes from
Learned borrowing from Sanskrit सं॒धि (saṃdhí, literally “junction; union”). Partial piecewise doublet of synthesis and synth.
Adapted from the Wiktionary entry sandhi (CC BY-SA 4.0).