Showing rather large events staged around one (9)

'showing rather' is the definition.
'ostensive' can be an answer for 'showing' (both can mean indicating or demonstrative). I am not sure about the 'rather' bit.

'large events staged around one' is the wordplay.
'large' becomes 'os' (abbreviation for oversize).
'staged' is an anagram indicator ('staged' can mean 'organised').
'around' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'events' is an anagram of '[events]'.
'os'+'[events]'='os[events]'
'ostensve' placed around 'i' is 'OSTENSIVE'.

Can you help me to learn more?