old man

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Slang One's father.
• noun Slang One's husband or boyfriend.
• noun A man in authority; a boss.
• noun The commanding officer, especially of a US naval vessel.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An elderly man.
• noun slang One's father.
• noun slang, US a husband, or significant other
• noun slang, US Military Unit's Commanding Officer.
• noun UK, dated Term of address for a male friend.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a familiar term of address for a man
• noun a man who is very old
• noun aromatic herb of temperate Eurasia and North Africa having a bitter taste used in making the liqueur absinthe
• noun an informal term for your father
• noun (slang) boss