What is the meaning of Seiner?

A fisherman who uses a seine to catch fish.

A fishing vessel used for seining.

his

to seine (fish using a seine)

his (substantival possessive)

genitive of er

genitive of es

inflection of sein:

  1. genitive/dative feminine singular
  2. genitive plural

genitive/dative feminine singular

genitive plural

Source: wiktionary.org