впервые

см. тж. первый

• Saturn's rings were first (or originally) discovered by Huyghens.

• We define each term when it is first used.

• D. was the first to establish this fact.

• The first experiment to be carried out with this apparatus took place in Prague.

• By effectively eliminating Doppler broadening this laser technique enables one for the first time to resolve the fine structure of these spectral lines.