Figure it to follow the archaeological work (5)
I believe the answer is:
digit
'figure' is the definition.
(thesaurus)
'it to follow the archaeological work' is the wordplay.
'to follow' means one lot of letters go next to another.
'the archaeological work' becomes 'dig'.
'it' after 'dig' is 'DIGIT'.
(Other definitions for digit that I've seen before include "a number less than ten" , "Single numeral" , "Single number" , "Like It?" , "Need a bit of a hand" .)