Someone who is very arrogant and assumes they know all the answers is an example of cocky.
Origin of cocky; from cock + -y
- Abbreviation of cockatoo; used when pretending to talk to such a bird, as in "hello cocky".
- (Australia, New Zealand, colloquial) A cockatoo farmer.
- (New Zealand, informal) A sheep farmer.
- (farmer): In both Australia and New Zealand, forms such as sheep cocky (sheep farmer) and cow cocky (dairy farmer) exist. In New Zealand, cocky is often synonymous with sheep cocky, due to the relative importance of the industry.
From cockatoo (“type of bird”) + -y (“diminutive suffix”).
From cocksure + -y (“having quality of”).