Several seaweeds good in salad uncovered close to shore (5)
I believe the answer is:
algae
'several seaweeds' is the definition.
(type of seaweed)
'good in salad uncovered close to shore' is the wordplay.
'good' becomes 'g' (abbreviation).
'in' means one lot of letters goes inside another.
'uncovered' means to look at the middle letters.
'close to' indicates one should take the final letters (the close/ending of).
The middle of 'salad' is 'ala'.
The final letter of 'shore' is 'e'.
'g' inserted inside 'ala' is 'alga'.
'alga'+'e'='ALGAE'
(Other definitions for algae that I've seen before include "Type of seaweed" , "Seaweeds generally" , "'Simple plants, such as seaweed (5)'" , "Aquatic growths" , "Marine growths" .)