FROM STRONG’S HEBREW DICTIONARY (1890)

Strong’s Hebrew Dictionary (1890) — public domain, printed whole.

na' 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.