Meaning:

• Who
• Which
• What

The relative pronoun that connects a relative clause to a main clause, referring back to a noun or pronoun (called the antecedent).

It is distinct from ὅτι (“that,” introducing indirect speech) and from ὅς as an interrogative in older Greek (meaning “who?”), which in Koine is usually τίς.

The relative pronoun agrees with its antecedent in gender and number, but its case depends on its role in its own clause. That is, the case of ὅς, ἥ, ὅ is determined by its function in the relative clause, not by the antecedent. For example, ἔγνω τὸν ἄνθρωπον ὅς ἐλάλησεν → “He knew the man who spoke.” (ὅς is nominative because it is the subject of ἐλάλησεν)