Chief Petty Officer
A chief petty officer is a senior non-commissioned officer
Non-commissioned officer
A non-commissioned officer , called a sub-officer in some countries, is a military officer who has not been given a commission...

 in many navies and coast guards.
"Chief Petty Officer" refers to two ranks in the Canadian Navy
Canadian Forces Maritime Command
The Royal Canadian Navy , is the naval force of Canada. The RCN is one of three environmental commands within the unified Canadian Forces. Operating 33 warships and several auxiliary vessels, the Royal Canadian Navy consists of 8,500 Regular Force and 5,100 Primary Reserve sailors, supported by...

. Chief Petty Officer 2nd Class
Chief Petty Officer 2nd Class
Chief petty officer, 2nd class, CPO2, is a Naval non-commissioned member rank of the Canadian Forces. It is senior to the rank of petty officer 1st-class and its equivalents, and junior to chief petty officer 1st-class and its equivalents...

 (CPO2) (Premier maître de deuxième classe or pm2 in French
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

) is equivalent to a Master Warrant Officer
Master Warrant Officer
Master warrant officer is a senior military rank in the Canadian Forces, Singapore Armed Forces and the Israel Defense Forces.-Canadian Forces:...

 in the Army and Air Force, and Chief Petty Officer 1st Class
Chief Petty Officer 1st Class
Chief petty officer, 1st class, CPO1, is the most senior non-commissioned member rank of the Royal Canadian Navy. It is equivalent to a chief warrant officer in the Canadian Army and Royal Canadian Air Force...

 (CPO1) (Premier maître de première classe or pm1) is equivalent to a Chief Warrant Officer in the Army and Air Force.