flashboarding vs flashboard

flashboarding and flashboard both are nouns.

Word	Noun	Adjective	Verb	Adverb
flashboarding	Yes	No	No	No
flashboard	Yes	No	No	No

As nouns, flashboarding and flashboard are synonyms defined as:

flashboarding and flashboard: boarding place along the top of a dam to increase its height

flashboarding (noun)	flashboard (noun)
boarding place along the top of a dam to increase its height	boarding place along the top of a dam to increase its height