I am trying to understand the meaning of the idiom "gier und gar." I have serched per word and in the internet it is not clear.
I guess (also from the "bissig und bös" question) the poem you're translating is Yvan Goll's "Der Panama-Kanal". "gier und gar" actually is not an idiom in German, and a literal translation along the lines of greed and cooked doesn't make any sense - not even to a native speaker. gar has a meaning in some southern German dialects and Austrian German of ""nothing left" - Doesn't really fit here as well. After all, the author had a French/German (Lorraine) background. I don't think he would have used Bavarian/Austrian expressions.
The section is, in longer form
Wo aber Steinwust lag, mit grünem Mergel und Moor gefleckt,
War der Boden wie Aas so faul, und so gier und gar
Ging sein Fieberhauch, daß die Träume die er gebar,
Zu giftigen Schwaden wurden, von weißer Sonne umbleckt.
The gier und gar relates to the Fieberhauch from the jungle ground. My guess it is gierig und gärend, after all, Goll was an expressionist, so didn't have to stick too close to the language ;)
The literal translation greedy and fermenting doesn't really sound like poetry. I think the author's emphasis wasn't focussed on the literal meaning here, but rather on the impression the sound makes on the reader illustrating that fiendish environment.
In a translation, the alliteration would be important because the author uses that stylistic means throughout the whole poem, but I can't come up with a good and close one at the moment, so
greedy and moldy
messy and moldy
(to keep the alliteration) would maybe be - not so literal - translations. In my opinion, it's more the sound of it that counts rather than the exact meaning here.
Gier probably means it is somehow messy, here is an example for ships that are tumbling around:
On first read the "nothing left", @tofro mentions, made sense to me, like it describes some wasteland. But the whole "gier and gar" seems to be related to Fieberhauch, not to the floor.
But never heard that expression, would have never used it and doesn't really make sense to me. You should read some normal books! :)