Real Dictionary

plan
A plan is a method of achieving something that you have worked out in detail beforehand.
If you have plans, you are intending to do a particular thing.
countable noun: A plan of something that is going to be built or made is a detailed diagram or drawing of it.
verb: If you plan what you are going to do, you decide in detail what you are going to do, and you intend to do it.
verb: When you plan something that you are going to make, build, or create, you decide what the main parts of it will be and do a drawing of how it should be made.

plan in American English
a drawing or diagram showing the arrangement in horizontal section of a structure, piece of ground, etc.
to make a plan of (a structure, piece of ground, etc.)
intransitive verb: to make plans
noun: a scheme or method of acting, doing, proceeding, making, etc., developed in advance
transitive verb: to arrange a method or scheme beforehand for (any work, enterprise, or proceeding)

plan in British English
noun: a detailed scheme, method, etc, for attaining an objective
verb: to form a plan (for) or make plans (for)

plan in Insurance
noun: A plan is an insurance policy or contract, especially a life or health insurance policy.

plan- in American English
plano- (sense 1)
combining form