A figure that's small, still (5)
I believe the answer is:
seven
'a figure' is the definition.
(seven is a number)
'small still' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'still' becomes 'even' (synonyms).
's'+'even'='SEVEN'
'that's' is the link.
(Other definitions for seven that I've seen before include "- Against Thebes (Aeschylus)" , "Number of sins, seas or dwarves" , "number of swans aswimming" , "Numeral" , "So many ages of man (AYLI)" .)