Tried to speak in crowd (4)
I believe the answer is:
herd
'crowd' is the definition.
(I know that crowd can be written as herd)
'tried to speak' is the wordplay.
'tried' becomes 'heard' (as in trying or hearing in a trial).
'to speak' indicates a 'sounds like' (homophone) clue.
'heard' sounds like 'HERD'.
'in' acts as a link.
(Other definitions for herd that I've seen before include "Group of cows, elephants etc" , "Group of animals, cattle, say" , "The rabble" , "Host" , "Drove" .)