'To lob a ball' definitions:

Definition of 'To lob a ball'

From: GCIDE

Lob \Lob\, v. t. [imp. & p. p. Lobbed (l[o^]bd); p. pr. & vb. n. Lobbing.]
2. To let fall heavily or lazily. [1913 Webster]
And their poor jades Lob down their heads. --Shak. [1913 Webster]
2. to propel (relatively slowly) in a high arcing trajectory; as, to lob a grenade at the enemy. [PJC]
To lob a ball (Lawn Tennis), to strike a ball so as to send it up into the air. [1913 Webster]