Meaning of “lash” - Learner’s Dictionary

lash

verb uk us /læʃ/

[ I, T ] If wind or rain lashes against something, the wind or rain is very strong and hits or blows hard against it:

Rain lashed against the window.
Wind and heavy rain lashed the palm trees.
lash sth down/together, etc

to tie something firmly to something else:

The boxes had been lashed together with ropes.

(Definition of “lash verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)