1. Numeric, Prefix

   one; 1

   壱, 弌 and 壹 are used in legal documents

   それは壱万円と計算されている。

2. Noun which may take the genitive case particle 'no', Suffix

   best

3. Noun which may take the genitive case particle 'no'

   first; foremost

4. Noun

   beginning; start

5. Noun, used as a prefix

   a (single); one (of many)

   before a noun

6. Noun

   ace

   Card gamessee エース

7. bottom string (on a shamisen, etc.)

Also written １【いち】ichi、壱【いち】ichi、弌【いち】ichi、壹【いち】ichi