Beside edges of tablecloth spread crumbs (7)
I believe the answer is:
strewth
'crumbs' is the definition.
(both can be expressions of annoyance)
'beside edges of tablecloth spread' is the wordplay.
'beside' is a charade indicator (letters next to each other).
'edges of' says to hollow out the word (remove centre letters).
'spread' becomes 'strew' (to strew is to spread or scatter around).
'tablecloth' with its middle removed is 'th'.
'th' after 'strew' is 'STREWTH'.
(Other definitions for strewth that I've seen before include "blimey" , "Good grief!" , "mild oath" , "Aussie exclamation" , "Expression of surprise" .)