Cud-chewing mammal showed up by lake (5)
I believe the answer is:
camel
'cud-chewing mammal' is the definition.
I can't tell whether this defines the answer.
'showed up by lake' is the wordplay.
'showed up' becomes 'came' (to show up is to come or attend).
'by' means one lot of letters go next to another.
'lake' becomes 'L' (geographical abbreviation).
'came'+'l'='CAMEL'
Can you help me to learn more?
(Other definitions for camel that I've seen before include "Desert transport" , "Beastly type" , "Old WWI plane" , "quadruped" , "Humped animal" .)