Definition of "sealer" [seal•er•sealer]

• One that seals, as an undercoat of paint or varnish used to size a surface. (noun)
• An officer who inspects, tests, and certifies weights and measures. (noun)
• One that is engaged in the hunting of seals. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The sealer is added last to prevent the formation of lumps in the mixture."
• "I know that roof sealer is similar with Marmolite (a fine white sand or marble powder) added."
• "The sealer is diluted into the slurry a ratio of four parts slurry to one part sealer."