Definify.com
Webster 1913 Edition
Carboxide
Car-box′ide
,Noun.
 [
Carbon 
+ oxide
.] (Chem.) 
A compound of carbon and oxygen, as carbonyl, with some element or radical; 
as, potassium 
. carboxide
Potassium carboxide
, a grayish explosive crystalline compound, 
 C6O6K
, obtained by passing carbon monoxide over heated potassium.