Update glossary.md

Author: mark-i-m

src/glossary.md

@@ -7,7 +7,7 @@ Term                    | Meaning
 ------------------------|--------
 AST                     |  the abstract syntax tree produced by the syntax crate; reflects user syntax very closely.
 codegen unit            |  when we produce LLVM IR, we group the Rust code into a number of codegen units. Each of these units is processed by LLVM independently from one another, enabling parallelism. They are also the unit of incremental re-use.
-completeness            |  soundness is a technical term in type theory. Completeness means that every type-safe program also type-checks. Having both soundness and completeness is very hard, and usually soundness is more important. (see "soundness").
+completeness            |  completeness is a technical term in type theory. Completeness means that every type-safe program also type-checks. Having both soundness and completeness is very hard, and usually soundness is more important. (see "soundness").
 cx                      |  we tend to use "cx" as an abbrevation for context. See also `tcx`, `infcx`, etc.
 DAG                     |  a directed acyclic graph is used during compilation to keep track of dependencies between queries. ([see more](incremental-compilation.html))
 DefId                   |  an index identifying a definition (see `librustc/hir/def_id.rs`). Uniquely identifies a `DefPath`.