Nuqta (Hindi नुक़्ता, also नुक्ता nukta, from Arabicnuqta نقطة "dot") is a term for a diacritic mark introduced in Devanagari (and some other Indian scripts) used to represent sounds from other languages which do not have a native character. It takes the form of a dot placed below a character.
Examples from Devanagari are: क़ qa, ख़ा ḫa, ग़ ġa, ज़ za, ड़ ṛa, ढ़ ṛha, फ़ fa, modifying क ka, ख kha, ग ga, ज ja, ड ḍa, ढ ḍha, फ pha, respectively. These phonemes have marginal existence in Hindi, occurring in some Perso-Arabic loanwords. The term nuqta नुक़्ता itself is an example; other examples include क़िला (قلعہ) qila "fortress", and आग़ा ख़ान Aga Khan (آغا خان, combination of a Perso-Arabic (aga) and a Turko-Mongolic (khan) honorific, now the title of the leader of the Nizari Ismaili sect. The nuqta, and the phonological distinction it represents, is often just ignored in practice, i.e. क़िला qila can simply be spelled as a Hindi word किलाkila, .The prescriptive modern Hindi grammar by Vajpeyi (1957ff.) allows for the nuqta in only two letters, ड़ ṛa and ढ़ ṛha, arguing that the other letters written with nuqta show no phonological differentiation in spoken Hindi, so that writing the nuqta would be just a pedantic exercise in orthography, or etymology. But this is now complicated by a renewed Hindi-Urdu language contact, as Urdu writers publish their works in Devanagari editions. Since the Perso-Arabic orthography is preserved in Nastaʿlīq script Urdu orthography, these writers tend to express the distinction in Devanagari as well, using the nuqta.