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Understood by is the most popular phrase on the web.

Defined by 18,600,000 results on the web	Understood by 139,300,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
b. To specify distinctly: define the weapons to be used in limited warfare. 3. To give form or meaning to: "For him, a life is defined by action" (Jay Parini). v.intr. size polished stone. Periods when children may be sensitive�... b. To specify distinctly: define the weapons to be used in limited warfare. 3. To give form or meaning to: "For him, a life is defined by action" (Jay Parini). v.intr. Two upper patio areas are defined by a redwood deck and granite pavers surrounded by medium 18 hours ago ... Logic's legacy defined by more than big numbers. Women's basketball: Career assist leader has brought toughness, leadership to Hawkeyes.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

Defined by

18,600,000 results on the web

Understood by

139,300,000 results on the web

More popular!

b. To specify distinctly: define the weapons to be used in limited warfare. 3. To give form or meaning to: "For him, a life is defined by action" (Jay Parini). v.intr.
size polished stone. Periods when children may be sensitive�...
b. To specify distinctly: define the weapons to be used in limited warfare. 3. To give form or meaning to: "For him, a life is defined by action" (Jay Parini). v.intr.
Two upper patio areas are defined by a redwood deck and granite pavers surrounded by medium
18 hours ago ... Logic's legacy defined by more than big numbers. Women's basketball: Career assist leader has brought toughness, leadership to Hawkeyes.

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.