One spotted in woods? Amphibian's also seen by lake (9)
I believe the answer is:
toadstool
'one spotted in woods?' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'amphibian's also seen by lake' is the wordplay.
'amphibian's' becomes 'toads' (toad is a kind of amphibian**).
'also' becomes 'too' ('too' can be a synonym of 'also').
'seen by' is a charade indicator (letters next to each other).
'lake' becomes 'l'.
'toads'+'too'+'l'='TOADSTOOL'
Can you help me to learn more?
(Other definitions for toadstool that I've seen before include "Umbrella-shaped fungus" , "Poisonous fungus" , "Fungal growth" , "what's poisonous maybe" , "that could be poisonous" .)