The best boat sails on a regular basis, avoiding strong waters (8)
I believe the answer is:
teetotal
'avoiding strong waters' is the definition.
I can't tell whether this definition defines the answer.
'the best boat sails on a regular basis' is the wordplay.
'on a regular basis' means one should take alternating letters.
'the'+'best'+'boat'+'sails'='thebestboatsails'
The alternating letters of 'thebestboatsails' are 'TEETOTAL'.
Can you help me to learn more?
(Other definitions for teetotal that I've seen before include "Abstaining completely from alcohol" , "Abstemious" , "Abstention from alcoholic drink" , "Avoiding alcohol" , "avoiding any possibility of inebriation" .)