"寡妇所得遗产" can be translated into English as "inheritance received by a widow" or more concisely as "a widow's inheritance".
"inheritance received by a widow" clearly specifies who receives the inheritance (a widow) and what it is (inheritance).
"a widow's inheritance" is a more idiomatic and concise expression, using the possessive form ("widow's") to indicate ownership or association.
Both translations are accurate, but the choice may depend on the context and the desired level of formality or conciseness.