What's the difference between まだ and いまだ（に）?


My intuition _wants_ to believe that `いまだに` is more formal, but all the
examples I've seen do not indicate that. Are they freely interchangeable?
Can't say I've ever heard `いまだに` in spoken context (or ever really seen it
often in written context either).




Originally there was only imada. It is a compound of the noun ima (今) and the
stem of the particle
[dani](http://dic.yahoo.co.jp/dsearch?enc=UTF-8&p=%E3%81%A0%E3%81%AB&dtype=0&dname=0na&stype=1&pagenum=1&index=11571400),
da. It has two primary meanings: 1) not yet 2) still. When used in the
positive sense 2), it emphasizes a continuation from the past.

mada is a contraction from imada. It is much more colloquial than the former.
While they both share these two meanings, mada has evolved a number of other
finer
[senses](http://dic.yahoo.co.jp/dsearch?enc=UTF-8&stype=1&dtype=0&dname=0ss&p=%E3%81%BE%E3%81%A0).
As a result, imada is now most associated and used for its negative sense "not
yet".

Note that 未 is always given the reading "imada... -zu" in 漢文 texts and means
"not yet", never "still". This is origin of words such as 未来 (未だ来ず imada ko-
zu, that which has not yet come --> the future).




Originally there was only imada. It is a compound of the noun ima (今) and the
stem of the particle
[dani](http://dic.yahoo.co.jp/dsearch?enc=UTF-8&p=%E3%81%A0%E3%81%AB&dtype=0&dname=0na&stype=1&pagenum=1&index=11571400),
da. It has two primary meanings: 1) not yet 2) still. When used in the
positive sense 2), it emphasizes a continuation from the past.

mada is a contraction from imada. It is much more colloquial than the former.
While they both share these two meanings, mada has evolved a number of other
finer
[senses](http://dic.yahoo.co.jp/dsearch?enc=UTF-8&stype=1&dtype=0&dname=0ss&p=%E3%81%BE%E3%81%A0).
As a result, imada is now most associated and used for its negative sense "not
yet".

Note that 未 is always given the reading "imada... -zu" in 漢文 texts and means
"not yet", never "still". This is origin of words such as 未来 (未だ来ず imada ko-
zu, that which has not yet come --> the future).

