1. [n]  witty remark
2. [n]  a witty saying
3. [v]  make jokes or quips; "The students were gagging during dinner"

QUIP is a 4 letter word that starts with Q.

1. \Quip\, n. [Cf. W. chwip a quick flirt or turn, chwipio to
   whip, to move briskly, and E. whip. Cf. {Quib}, {Quibble}.]
   A smart, sarcastic turn or jest; a taunt; a severe retort; a
   gibe.
   
         Quips, and cranks, and wanton wiles.     --Milton.
   
         He was full of joke and jest, But all his merry quips
         are o'er.                                --Tennyson.
   
   

2. \Quip\, v. t. [imp. & p. p. {Quipped}; p. pr. & vb. n.
   {Quipping}.]
   To taunt; to treat with quips.
   
         The more he laughs, and does her closely quip.
                                                  --Spenser.
   
   

3. \Quip\, v. i.
   To scoff; to use taunts. --Sir H. Sidney.