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Study Dictionary
Radiant
RADIANT [ISBE]
RADIANT - ra'-di-ant (nahar, "to sparkle" i.e. (figurative) be cheerful; hence (from the sheen of a running stream), to flow, i.e. (figurative) assemble; flow (together), be lightened): the American Standard Revised Version substitutes the active "radiant" for the passive "were lightened" in Ps 34:5; Isa 60:5 (English Revised Version, the King James Version "flow together"). As the earth and moon, both being dark, face a common sun and lighten each other, they are not only lightened, but radiant. So with the believers, "They looked unto him (Yahweh), and were radiant." Thus nahar combines the two ideas of being lightened and flowing together. This appears, also, in a different connection, in Isa 60:5, "Then thou shalt see and be radiant." "It is liquid light--light that ripples and sparkles and runs across the face; .... the light which a face catches from sparkling water" (G.A. Smith, Isaiah, II, 430).M. O. Evans
Also see definition of "Radiant" in Word Study