Note that "individual" in this definition does not mean simply "single, separate" but rather something like "be attributable to something or someone" or "be uniquely associated with something or someone."

DujwIj tlhIn
"my particular ship, my own ship"

betleHlIj vIneHbe', betleHwIj tlhIn vIghaj
"I don't want your bat'leth, I have my own bat'leth"

Even with this word, it gets confusing when third person is involved, since, there could be two different third persons.

DujDaj legh HoD
"The captain sees his/her ship."

This could mean that the captain sees his/her own ship or sees somebody else's ship.

Adding tlhIn doesn't help: DujDaj tlhIn legh HoD could mean either "The captain sees his/her own ship" or else "The captain sees his/her particular ship" (when we know that, in this case, "his/her" refers to someone other than the captain). This confusion arises, however, only when at least one of the third persons is referred to pronominally only. If nouns are used, the ambiguity goes away:

jagh Duj tlhIn legh HoD
"The captain sees the enemy's own ship"

HoD Duj tlhIn legh HoD
"The captain sees the captain's own ship."

Aha, you say, if there are two captains, it's still ambiguous. And you are correct, but it has nothing to do with "own". You'd have to distinguish them in the discourse anyway to avoid ambiguity.

HoD qan Duj legh HoD Qup
"The young captain sees the old captain's ship"

HoD qan Duj tlhIn legh HoD Qup
"The young captain sees the old captain's own ship"

HoDlI' Duj tlhIn legh HoDwI'
"My captain sees your captain's ship"

HoDlI' Duj tlhIn legh HoDwI'
"My captain sees your captain's own ship"

When there's only one captain being talked about in the discussion, there's no ambiguity:

DujDaj tlhIn legh HoD
"The captain sees his/her own ship"

This isn't ambiguous as long as in the discourse or conversation there is only one captain and only one possible referent for "his/her".

That is, this lack of ambiguity is due to context, a consideration not possible with a single sentence in isolation. If someone said, out of the blue (out of context), DujDaj tlhIn legh HoD, this would be ambiguous. But except in language classes and things like that, people generally don't talk in individual sentences out of the blue.