Wordnet 3.0
ADJECTIVE (1)
1.
such that the terms of an expression cannot be interchanged without changing the meaning;
- Example: "the arguments of the symmetric relation, `is the father of', are noninterchangeable"
The Collaborative International Dictionary of English v.0.48:
noninterchangeable \noninterchangeable\ adj.
1. (math, logic) not able to be interchanged without changing
the truth value.
[WordNet 1.5]
2. Not able to be substituted for each other; -- of objects,
such as parts of machinery; as, the ink cartidges on the
new printer are noninterchangeable with those on the older
model.
[PJC]
WordNet (r) 3.0 (2006):
noninterchangeable
adj 1: such that the terms of an expression cannot be
interchanged without changing the meaning; "the arguments
of the symmetric relation, `is the father of', are
noninterchangeable"