The last lair at the gallery has no teeth (8)
I believe the answer is:
edentate
'has no teeth' is the definition.
I can't tell whether this defines the answer.
'the last lair at the gallery' is the wordplay.
'last' indicates one should take the final letters.
'lair' becomes 'den' (synonyms).
'at' is a charade indicator (letters next to each other).
'the gallery' becomes 'tate' (Tate Modern, Tate Britain etc).
The final letter of 'the' is 'e'.
'e'+'den'+'tate'='EDENTATE'
Can you help me to learn more?
(Other definitions for edentate that I've seen before include "Animal as sloth, armadillo" , "sloth, say" , "Toothless creature" , "teeth? None" , "Mammal such as sloth or anteater" .)