The most up-to-date and thorough interpretive dictionary (or lexicon) devoted to NT words is the New International Dictionary of New Testament Theology and Exegesis (NIDNTTE). This dictionary is available online for UNW students and faculty. It is a different kind of dictionary than most language dictionaries and lexicons. In particular, it focuses on the historical and theological meanings of a word or word-group used in the NT. The entries read more like word histories with interpretations of words in specific NT contexts. Each entry in the NIDNTTE typically follows this pattern:
The NIDNTTE is ordered alphabetically by Greek letter. If you don't know the Greek language, you should learn it. But even if you don't know Greek, this dictionary is still an accessible and valuable resource for English readers. Here's how to find your word or word-group.
Find the Strong's number. Each Greek work in the NT has a designated number. Most websites use the Strong's number. And some resources (like the NIDNTTE) use the GK number.
Find the GK number that corresponds to your Strong's number.
Find the entry for the word/word group in the NIDNTTE
If you have a translation other than an NIV or ESV (many students use the NASB or KJV) try to select a concordance that corresponds to that version (e.g., NASB use Strongest NASB Exhaustive Concordance (REF 220.2 N42s). There are several others on the shelf, all of which use the Strong's numerical system. Be sure to choose one that uses your translation.