22d
Victim of Roman army on borders of Iberia
?OSTIA.
I think it's Hostia (host =victim)+IA ( bordering letters of Iberia )
But I can't find it in Chambers .
Could an Azeder confirm please .
It's in Chambers under 'host' third meaning (sacrificial victim) as the etymology at the end of the definition - see Azed's note at the end of the crossword entries.