Merriam-Webster's Collegiate® Dictionary, 11th Edition
WHILE
I. noun
Etymology: Middle English, from Old English hwīl; akin to Old High German hwīla time, Latin quies rest, quiet Date: before 12th century a period of time especially when short and marked by the occurrence of an action or a condition ; time , the time and effort used (as in the performance of an action) ; trouble ,
II. conjunction
Date: 12th century
1. during the time that , as long as ,
2. when on the other hand ; whereas , in spite of the fact that ; although , similarly and at the same time that ,
III. preposition
Date: 15th century
until ,
IV. transitive verb (whiled; whiling)
Date: 1635
to cause to pass especially without boredom or in a pleasant manner