-i and -u stems

So far, we have learned about two different stem families. The first, which is the family of -a stems, contains masculine and neuter stems. The second, which is the family of -ā, -ī, and -ū stems, mostly contains feminine stems.

Now we will learn about the family of -i and -u stems. These stems can be masculine, feminine, or neuter. That is, they can appear in any of the three genders.

Basic -i stems

In the examples below, we will use the adjective stem śuci, which means “shining,” “clear,” or “pure.”

First, here is the pattern for masculine stems:

The endings here are mostly similar to the basic nominal endings. But there are some important differences. For the singular forms, notice that cases 3 and 4 show slight changes. Case 3 has an extra n sound, and in case 4 the i of śuci strengthens to śuce, which then combines by normal sandhi rules:

• शुचिना शुचये
  śucinā śucaye
  (śuci, singular, in cases 3 and 4)
  

• नावा नावे
  nāvā nāve
  (nau, singular, in cases 3 and 4)
  

In cases 5 through 8, we have various differences with no clear pattern:

• शुचेः शुचेः शुचौ शुचे
  śuceḥ śuceḥ śucau śuce
  (śuci, singular, in cases 5 through 8)
  

• नावः नावः नावि नौः
  nāvaḥ nāvaḥ nāvi nauḥ
  (nau, singular, in cases 5 through 8)
  

For the dual forms, notice the long ī in śucī. And for the plural forms, notice that cases 2 and 6 resemble the -a stems:

• शुचीन् शुचीनाम्
  śucīn śucīnām
  (śuci, plural, in cases 2 and 6)
  

• गजान् गजानाम्
  gajān gajānām
  (gaja, plural, in cases 2 and 6)
  

Feminine stems follow a pattern similar to the masculine stems. But in cases 4 through 7, they can optionally behave as if they end with -ī:

Note that the case 2 feminine plural is śucīḥ as opposed to the masculine śucīn.

The neuter stem uses the basic nominal endings. But if an ending starts with a vowel, we add an extra n sound. We also use -īnām with a long -ī, just as we did above:

Again, notice that the neuter stem uses a long vowel with an extra nasal sound:

• मनस् + इ → मनांसि
  manas + i → manāṃsi
  

• फल + इ → फलानि
  phala + i → phalāni
  

• शुचि + इ → शुचीनि
  śuci + i → śucīni
  

Basic -u stems

In the examples below, we will use the adjective stem madhu, which means “sweet.” If used in the neuter gender, it can also mean “honey.”

The masculine endings follow the same pattern as the -i endings we saw above. Where -i becomes y or ay or e, -u becomes v or av or o:

But note that the case 7 singular is -au for both -i stems and -u stems:

• शुचौ
  śucau
  in the clean (thing)
  

• मधौ
  madhau
  in the sweet (thing)
  

The feminine endings are similar to the endings we saw above. This includes the optional forms in the singular of cases 4 to 7, which might act like -ū stems:

Like before, note that the case 2 feminine plural is madhūḥ as opposed to the masculine madhūn.

The neuter endings are again similar to what we saw above:

Review

If you are tempted to memorize these endings, we urge you instead to work on acquisition.

1. The feminine -i and -u have optional forms for certain cases and numbers. Which cases and numbers?