Strong's #4994: na' (pronounced naw)
a primitive particle of incitement and entreaty, which may usually be rendered: "I pray," "now," or "then"; added mostly to verbs (in the Imperative or Future), or to interjections, occasionally to an adverb or conjunction:--I beseech (pray) thee (you), go to, now, oh.
Brown-Driver-Briggs Hebrew Lexicon:
nâ'
1) I (we) pray, now, please
1a) used in entreaty or exhortation
Part of Speech: participle
Relation: a primitive particle of incitement and entreaty, which may usually be rendered: "I pray," "now," or "then"
Usage:
This word is used 403 times:
Malachi 1:8: "is it not evil? offer it now unto thy governor; will he be pleased with thee, or accept"
Malachi 1:9: "And now, I pray you, beseech God that he will be gracious unto us: this hath been by your means:"
Malachi 3:10: "that there may be meat in mine house, and prove me now herewith, saith the LORD"