Dancing rumba without a singer for protection (8)
I believe the answer is:
Here is my best explanation:
'protection' is the definition.
(umbrella is a kind of protection)
'dancing rumba without a singer' is the wordplay.
'dancing' indicates an anagram.
'without' suggests deleting specific letters.
'singer' becomes 'ella' (Ella Fitzgerald).
'rumba' with 'a' taken away is 'rumb'.
'rumb' anagrammed gives 'umbr'.
'for' acts as a link.
(Other definitions for umbrella that I've seen before include "requirement in poor weather", "protective cover", "Brolly", "Collapsible ribbed canopy against rain", "Portable, protective canopy", "Protective canopy", "Handheld collapsible canopy", "Canopy", "Parasol" and "Portable device giving protection against rain etc".)