Real Dictionary

Ar.M. in American English
abbreviation: Master of Architecture

ARM in American English
abbreviation: adjustable-rate mortgage
abbreviation: Armenian

arm in American English 1
an upper limb of the human body
noun: the upper limb of the human body, esp. the part extending from the shoulder to the wrist

arm in American English 2
any instrument used in fighting; weapon
to provide with weapons, tools, etc.
noun: weapons, esp. firearms

ARM in British English
abbreviation for: adjustable rate mortgage

arm in British English 1
noun: (in humans) either of the upper limbs from the shoulder to the wrist

arm in British English 2
to equip with weapons as a preparation for war
noun: a weapon, esp a firearm

ARM in Finance
abbreviation: ARM is a type of mortgage where the interest rate may change according to changes in other rates.

arm part of your body or of something else
An arm of an organization is a section of it that operates in a particular country or that deals with a particular activity.
Your arms are the two long parts of your body that are attached to your shoulders and that have your hands at the end.
countable noun: An arm of an object is a long thin part of it that sticks out from the main part.
countable noun: An arm of land or water is a long thin area of it that is joined to a broader area.
countable noun: The arm of a chair is the part on which you rest your arm when you are sitting down.
countable noun: The arm of a piece of clothing is the part of it that covers your arm.

arm weapons
Arms are weapons, especially bombs and guns.

Arm. in American English
abbreviation: Armenian

Arm. in British English
abbreviation for: Armenia(n)