Tile set wrongly second time (7)
I believe the answer is:
tessera
'tile' is the definition.
(I've seen this before)
'set wrongly second time' is the wordplay.
'wrongly' is an anagram indicator.
'second' becomes 's' (common abbreviation).
'time' becomes 'era' (era is a kind of time).
'set' anagrammed gives 'tes'.
'tes'+'s'+'era'='TESSERA'
(Other definitions for tessera that I've seen before include "Die" , "Piece of picture" , "Small stone for mosaics" , "Bit of mosaic" , "Mosaic stone" .)