Clusters of two or more consonants form a ligature. Basically Oriya has two types of such consonant ligatures. The "northern" type is formed by fusion of two ore more consonants as in northern scripts like Devanāgarī (but to a lesser extent also in the Malayalam script in the south). In some instances the components can be easily identified, but sometimes completely new glyphs are formed. With the "southern" type the second component is reduced in size and put under the first as in the southern scripts used for Kannada and Telugu (and to some extent also for Malayalam script. The following table shows the most commonly used ligatures. (Different fonts may use different ligatures.)
The Oriya alphabet exhibits quite a few ambiguities which add to the difficulties beginners encounter in learning it.
Some of the letters of the script may easily be confounded. In order to reduce ambiguities a small oblique stroke is added at the lower right end as a diacritic. It resembles Halanta (Virāma) but it is joined to the letter, whereas Halanta is not joined. When the consonant forms a vowel ligature by which the lower right end is affected, this stroke is shifted to another position. This applies also to consonant ligatures baring the stroke (see table of consonant ligatures).
Some of the subjoined consonants, some other ligature components and variants of vowel diacritics have changing functions:
Open top consonants get a subjoined variant of the vowel diacritic for ⟨i⟩ as in
This same little hook is used in some consonant ligatures to denote ⟨t⟩ as first component:
The subjoined form of ⟨ch⟩ is also used for subjoined ⟨th⟩:
The subjoined form of ⟨bh⟩ serves also as a diacritic for different purposes:
The subjoined forms of ⟨ṇ⟩ and ⟨tu⟩ are almost identical:
The sign for the nasal ⟨ṁ⟩ may be used as a diacritic too: