public Builder mergeSourceTerm(com.google.cloud.translate.v3.GlossaryTerm value) {
        if (sourceTermBuilder_ == null) {
          if (((bitField0_ & 0x00000001) != 0)
              && sourceTerm_ != null
              && sourceTerm_ != com.google.cloud.translate.v3.GlossaryTerm.getDefaultInstance()) {
            getSourceTermBuilder().mergeFrom(value);
          } else {
            sourceTerm_ = value;
          }
        } else {
          sourceTermBuilder_.mergeFrom(value);
        }
        if (sourceTerm_ != null) {
          bitField0_ |= 0x00000001;
          onChanged();
        }
        return this;
      }
<pre>
The source term is the term that will get match in the text,
</pre>

<code>.google.cloud.translation.v3.GlossaryTerm source_term = 1;</code>
java-translate/proto-google-cloud-translate-v3/src/main/java/com/google/cloud/translate/v3/GlossaryEntry.java