Located next to the word 'purchased' is a subscript 'c'. When one looks to the cross-references in the left hand margin under 1:14 you see the transliterated Greek word apolutrōsis followed by the Strong's # 0629. When one turns to the lexicon (2,221), the entry looks like this:
I find this feature most helpful for pastors and educated lay folk who may lack acumen in the languages. This is not to say that the lexicon is comprehensive, 100 words are listed for both the Hebrew and Greek lexicons, but many key words are honed in on and elucidated, making this a very valuable feature.
Postscript: I had the opportunity to share the NLT Study Bible with my Romans class and the reaction was overwhelmingly positive. I believe this is just what folks have been looking for in a study bible and more.
I will have futher comments when the ESV Study Bible makes its debut, and will compare and contrast their respective features.