while

prep. until (Archaic)

v. spend time; pass time

conj. during, at the same time as; as long as; despite; if

n. time; period of time; short time; few moments; effort

While and whilst are conjunctions whose primary meaning is "during the time that". An example is:The days were hot while we were on vacation.While and whilst can nowadays legitimately be used in the contrastive sense of although or whereas, provided that it is not ambiguous (although some commentators, such as Eric Partridge, have frowned upon such use):While I am here, I can call home.This sentence can mean either "During the time that I am here, I can call home" or "although I am here, I can call home". Alternatively, in some Northern English and Scottish English dialects, while (but not whilst) usually takes the meaning of until, as in: "I shall wait while you are ready."
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(v. t.)
To cause to pass away pleasantly or without irksomeness or disgust; to spend or pass; -- usually followed by away.
  

(v. i.)
To loiter.
  

(prep.)
Until; till.
  

(n.)
That which requires time; labor; pains.
  

(n.)
Space of time, or continued duration, esp. when short; a time; as, one while we thought him innocent.
  

(conj.)
Hence, under which circumstances; in which case; though; whereas.
  

(conj.)
During the time that; as long as; whilst; at the same time that; as, while I write, you sleep.
  

<programming> The loop construct found in nearly all imperative programming languages which executes one or more instructions (the "loop body") repeatedly so long as some condition evaluates to true. In contrast to a repeat loop, the loop body will not be executed at all if the condition is false on entry to the while.
For example, in C, a while loop is written
while () ;
where is any expression and is any statement, including a compound statement within braces "..".
(1995-03-14)

Noun
1. a period of indeterminate length (usually short) marked by some action or condition; "he was here for a little while"; "I need to rest for a piece"; "a spell of good weather"; "a patch of bad weather"
(synonym) piece, spell, patch
(hypernym) time
(hyponym) cold spell, cold snap