/ Dictionary / Index B building line: Meaning and Definition of Find definitions for: build'ing line" Pronunciation: [key] (on a building lot) a line within, or coinciding with, the property line, beyond which it is illegal to build. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. building code building paper Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language