term:

Dilution

dilution n

1 : a lessening of real value (as of equity) by a decrease in relative worth
;specif
: a decrease of the value per share of common stock caused by an increase in the total number of shares
2 : a lessening of the value of a trademark that is caused by use of the mark by another and that creates potential confusion on the part of the consumer
3 : a weakening of the voting rights of a group of citizens (as a minority) because the representatives they elect have no greater legislative power than the representatives elected by smaller voting groups

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.