Strong G109 ἀήρ aēr · air

1 Corinthians

1. 1 Corinthians 9:26
   I therefore so run, not as uncertainly; so fight I, not as one that beateth the air:
2. 1 Corinthians 14:9
   So likewise ye, except ye utter by the tongue words easy to be understood, how shall it be known what is spoken? for ye shall speak into the air.