12 letter X word | 
                  Scrabble® | 
                  Words With Friends® | 
                  Description | 
                
|---|---|---|---|
| conservatrix | 31 | 27 | a female conservator... | 
| heteroduplex | 31 | 27 | a nucleicacid molecu... | 
| hypercomplex | 44 | 36 | excessively complex... | 
| morphosyntax | 37 | 30 | the study of the int... | 
| plagioclimax | 36 | 32 | the climax stage of... | 
| pneumothorax | 30 | 29 | accumulation of air... | 
| portmanteaux | 28 | 27 | PORTMANTEAU, (French... |