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P. and V. ἕως, ἐν ᾧ. Ar. and P. ἐν ὅσῳ, V. ἔστε (also Xen.).
for a while, adv.: P. and V. τέως.
for a long while: P. and V. μακρὸν χρόνος; see long.
it is worth while: P. and V. ἄξιόν ἐστι (or omit ἐστι) (with infin.).
while away: P. and V. τρίβειν, διάγειν; see spend.