It is absolutely necessary when drafting a contract to use accurate terminology in order prevent any misunderstandings or misinterpretations. Words can be easily misused, incorrectly substituted as synonyms, or placed in the wrong context. Drafts should be proofread several times by at least one neutral party, long before there are thoughts of a finalized formal document. Very much like those college professors who warned all semester, “you can’t write this paper well if you decide to start at four in the morning before the deadline”, a solid contract must go through a rigorous revision process before it can provide the desired results. The anecdotal college paper might very well get a passing grade; but a contract is more than a paper. It is the foundation on which every single aspect of an agreement rests.

There are many, many terms that people regularly. The following list is certainly not an exhaustive compilation, but it may be a helpful place to begin.

Affect: To alter, influence, or change
Effect: A result, or to bring about change

Alternate: A substitute or second choice, or to take turns
Alternative: One choice among various options

Among: Occurring in a group of three or more
Between: Occurring in a set of two

Assure: To convince
Insure: To guard against loss

Assure: To convince
Ensure: To make certain

Bimonthly: Every other month
Semimonthly: Twice a month

Biweekly: Every other week
Semiweekly: Twice a week

Capital: City that is the seat of local government, or relating to money, or an uppercase letter
Capitol: The building in which the legislature meets

Continual: Intermittent or repeated at intervals
Continuous: Without interruption

Discreet: Prudent or cautious
Discrete: Separate or detached 

Eminent: High in rank
Imminent: About to occur

Farther: Greater distance
Further: Greater degree, time, or quantity

Fewer: A smaller number of units
Less: A smaller quantity

i.e.: That is
e.g.: For example

Imply: To suggest
Infer: To conclude

Its: Belonging to it
It's: It is

Mean: The number obtained by adding all values together and dividing by the number of values
Median: The value that falls in the middle of all of the recorded values, with an equal number of values above and below it

Practical: Useful in actual practice
Practicable: Capable of being put into practice

Principal: Head or chief
Principle: A basic truth or assumption

Stationary: Fixed or immovable
Stationery: Writing materials