- carpet-shark
- carpet-snake
- carrier
- carrot, native
- cascarilla, native
- cassowary
- casuarina
- cat-bird
- cat-fish
- cat, native
- catholic frog
- cat's eyes
- cat's-head fern
- catspaw
- cat's tail
- cattle-bush
- cattle-duffer
- cattle-racket
- caustic-creeper
- caustic-vine
- caustic-plant
- cavally
- cedar
- celery, australian
- celery-topped pine
- centaury, native
- centralia
- cereopsis
- channel-bill
- cheesewood
- cherry, herbert river
- cherry, native
- cherry-picker
- chestnut pine
- chewgah-bag
- chinkie
- chock-and-log
- choeropus
- Christmas
- christmas-bush
- christmas-tree
- chucky-chucky
- chum
- chy-ack
- cicada
- cider-gum
- cider-tree
- city
- claim
- clay-pan
- clear-skins
- clean-skins
- clearing lease
- clematis
- clianthus
- climbing-fish
- climbing-pepper
- clitonyx
- clock-bird
- clock, settlers'
- cloudy-bay cod
- clover-fern
- clover, menindie
- clover-tree
- coach
- coach-whip bird
- coast
- coaster
- cobb
- cobbler
- cobblers-awl
- cobbler's pegs
- cobbra
- cock-a-bully
- cockatiel
- cockatoo
- cockatooer
- cockatoo fence
- cockatoo bush
- cockatoo orchis
- cock-eyed bob
- cockle
- cock-schnapper
- cod
- coffee-bush
- coffer-fish
- coffee berry
- coffee plant
- colonial experience
- colonial goose
- colour
- convictism
- coobah
- cooey
- coo-ee
- cooee, within
- cooee
- coo-in-new
- kooliman
- coolaman