halettan

From Proto-West Germanic *hailattjan, *hailittjan, *hailuttjan, from Proto-Germanic *hailatjaną, *hailitjaną, *hailutjaną (verbal suffix). From hāl +‎ -ettan.

hālettan

to hail, salute, greet
- Sum man hine hālette and grētte and hine be his naman nemde
  A certain man hailed and greeted him and called him by his name
- Iohannes hālette on hie mycelre stefne
  John saluted her with a great voice

Objects or pronouns were often used with the preposition on.
This was never used as a greeting or invocation like modern English hail, for this wes hāl (wassail), bēo hāl or bēo gesund were used, and ēalā was also used for invocations.

Conjugation of hālettan (weak, class 1)

More information infinitive, indicative mood ...

Old English