A few among meerkats, ever alert (7)
I believe the answer is:
several
'a few' is the definition.
(I've seen this before)
'among meerkats ever alert' is the wordplay.
'among' indicates the answer is hidden within the clue.
'SEVERAL' is hidden in the letters of 'meerkats ever alert'.
(Other definitions for several that I've seen before include "Some participants" , "three or four" , "Divers" , "A few; separate" , "A good few" .)