flow diagram vs flowchart

flow diagram and flowchart both are nouns.

Word	Noun	Adjective	Verb	Adverb
flow diagram	Yes	No	No	No
flowchart	Yes	No	No	No

As nouns, flow diagram and flowchart are synonyms defined as:

flow diagram and flowchart: a diagram of the sequence of operations in a computer program or an accounting system

Other synonyms of flow diagram include flow chart, flow sheet.

flow diagram (noun)	flowchart (noun)
a diagram of the sequence of operations in a computer program or an accounting system	a diagram of the sequence of operations in a computer program or an accounting system