Wordnet 3.0
NOUN (1)
1. 
 liquid containing proteins and electrolytes including the liquid in blood plasma and interstitial fluid; 
- Example: "the body normally has about 15 quarts of extracellular fluid"[syn: extracellular fluid, ECF]
WordNet (r) 3.0 (2006):
ECF
    n 1: liquid containing proteins and electrolytes including the
         liquid in blood plasma and interstitial fluid; "the body
         normally has about 15 quarts of extracellular fluid" [syn:
         extracellular fluid, ECF]
V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):
ECF
       Enhanced Connectivity Facilities (IBM)