Real Dictionary

uniform in American English
always the same; not varying or changing in form, rate, degree, manner, etc.; constant
adjective: identical or consistent, as from example to example, place to place, or moment to moment
noun: an identifying outfit or style of dress worn by the members of a given profession, organization, or rank

uniform in British English
to fit out (a body of soldiers, etc) with uniforms
adjective: unchanging in form, quality, quantity, etc; regular
noun: a code word for the letter u
noun: a prescribed identifying set of clothes for the members of an organization, such as soldiers or schoolchildren

uniform in Hospitality
noun: A uniform is a special set of clothes which some people, for example staff in a hotel, wear to work.