be (one's) own master Идиома

ass master

jerk, idiot; term for someone you don't like

Dutch Master

Dutch Master is a brand of cigars. When rolling a serious blunt, the tobacco is removed from a cigar and replaced with marijuana:"Slit a nigga back like a Dutchmasta killa" -- Wu-Tang Clan (???)

a past master at

Idiom(s): be a past master at sth

Theme: SKILL

to have been proven extremely good or skillful at an activity.
• Mary is a past master at cooking omeletes.
• Pam is a past master at the art of complaining.

emcee|M.C.|ceremonies|master|master of ceremonies

n. The person in charge of introducing the various participants in a show or entertainment. Bob Hope was the M.C. of many memorable shows.

master copy|copy|master

n. 1. A perfect text to which all copies are made to conform; a corrected version used as a standard by printers. The master copy must be right, because if it isn't, the mistakes in it will be repeated all through the edition. 2. A stencil from which other copies are made. Mr. Brown told his secretary to save the master copy so that they could run off more copies whenever they needed them. The master copy was too light so many of the copies didn't come out clear.

master key|key|master

n. phr. A key that opens a set of different locks. The building janitor has a master key to all of the apartments in this building.

mastermind

n. A person who supplies the intelligence for a project and/or undertakes its management. Winston Churchill was the mastermind in the war against Hitler.

past master|master|past

n. phr. An expert. Alan wins so often because he is a past master at chess.

master

master
see past master.

past master

past master
A person who is thoroughly experienced or exceptionally skilled in some activity or craft. For example, We're lucky to get Ella, because she's a past master at fundraising. This expression probably alludes to the original literal meaning, that is, one who formerly held the post of master in a lodge or other organization. Although past mistress was used for an exceptionally skilled woman in the mid-1800s, it is heard less often today, master serving for both sexes. [Mid-1800s]