Approached large creature in desert? (5)
I believe the answer is:
camel
'creature in desert?' is the definition.
(some camels live in deserts)
'approached large' is the wordplay.
'approached' becomes 'came' (come can mean to approach or get closer).
'large' becomes 'L' (eg in clothes sizes).
'came'+'l'='CAMEL'
(Other definitions for camel that I've seen before include "Yellowish" , "Humped mammal" , "Humped creature" , "Cud-chewing mammal of desert regions" , "Humped ungulate" .)