This is the next to last field of the interlinear - one which can be leveraged to permit a wide variety of search conditions or visual filter conditions. The base resource is Louw, Johannes P., and Eugene Albert Nida. Greek-English Lexicon of the New Testament: Based on Semantic Domains. New York: United Bible Societies, 1996. to which the interlinear is keyed.
Additional reading:
1. Just as the Strong's number links to the Strong's lexicon, so the Louw-Nida links to the Louw-Nida lexicon. This lexicon is organized by semantic domain rather than the usual alphabetic lemma.

2. Note that the Context Menu gives you a direct link to the lexicon as well as the usual search options.

3. Note that the Search is slightly broader than the (reverse)interlinear Bibles as some apostolic fathers' works are also coded with LN numbers.

4. The Louw-Nida search argument may also be used in Visual Filters - I have the following obtained from the Faithlife Visual Filters group.

5. A screenshot of the relevant Faithlife group - care needs to be taken that you get the latest version as at least one of the early versions no longer works.

6. This filter indicates persons, places and things selecting by LN number. Note that the HCSB which has no reverse interlinear shows no results.

7. This filter translates the relationships included in the LN 89 semantic domain. Note how the filter ties the highlighting to the lexicon.

8. This filter highlights discourse analysis markers, encouraging the user to learn to do their own discourse analysis or at least review the analysis provided by Faithlife.

9. This filter highlights time and location markers. Change in time and location is one indicator of potential pericope boundaries. This highlights the text the user may focus on in choosing between alternative boundaries.

10. The final filter provides semantic role highlighting - based on case rather than the case frame foundations of the Faithlife semantic role coding.
