This is a non-standard shortening of the word iyon, which can be translated into English as ‘that.’
It should properly have an apostrophe before the letter “y” in order to indicate that it is a shortening; however, in short text messages and on social media, this rule is widely ignored.
Also often shortened to ‘yun in conversation.
Difference between iyan and iyon
iyan (near the person being addressed by a speaker)
iyon (far from the speaker and the person being addressed)
(What’s that you have there?)
(What’s that near you?)
(What’s that over there?)
The meaning really depends on the context.
Kailangan ko ‘yun.
I need it.
(something not immediately in front of the people talking)
Ano iyong kinain mo?
= Ano ‘yung kinain mo?
What was it that you ate?
Ginamit mo ba ‘yung lapis?
Did you use the pencil?
(here, the word is translated into English as ‘the‘)
Nakita mo ‘yung kotse?
Did you see the car?
The best way to learn in which context the word is used is to listen to a lot of Filipino conversation!