Emergency room supporting soldier with organ donor (6)

'donor' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'emergency room supporting soldier with organ' is the wordplay.
'emergency room' becomes 'ER' (abbreviation popularized by US TV series).
'supporting' means one lot of letters go next to another (in a down clue, some letters go below others).
'soldier' becomes 'gi' (term for US soldier).
'with' says to put letters next to each other.
'organ' becomes 'FT' (Financial Times - organ can mean a newspaper).
'gi'+'ft'='gift'
'er' after 'gift' is 'GIFTER'.

Can you help me to learn more?