Opener rebids his 6+ card suit:
South:
♠ A K 10 9 8 7 South North
♥ 8 5 1♠ 2♣
♦ A Q 7 2♠
♣ 5 2
South’s 2♠ bid after the 2/1 response shows a 6+ card suit.
However, if opener jumps in his original suit, it shows a solid 6+ card suit.