Synonyms of the word

impervious

• adj. Unaffected or unable to be affected by.
• adj. Preventive of any penetration; impenetrable, impermeable, particularly of water.
• adj. Immune to damage or effect.

acid-fast

• adj. (histology, of bacteria) Retaining stain when treated with an acidic solution.

colorfast

• adj. Having colors that have been dyed or applied to the material in a way that will prevent them from being…

fast

• adj. (dated) Firmly or securely fixed in place; stable.
• adj. Firm against attack; fortified by nature or art; impregnable; strong.
• adj. (of people) Steadfast, with unwavering feeling. (Now only in set phrases like "fast friend".).
• adj. Moving with great speed, or capable of doing so; swift, rapid.
• adj. Causing unusual rapidity of play or action.
• adj. (computing, of a piece of hardware) Able to transfer data in a short period of time.
• adj. Deep or sound (of sleep); fast asleep (of people).
• adj. (of dyes or colours) Not running or fading when subjected to detrimental conditions such as wetness or…
• adj. (obsolete) Tenacious; retentive.
• adj. (colloquial) Having an extravagant lifestyle or immoral habits.
• adj. Ahead of the correct time or schedule.
• adj. (of photographic film) More sensitive to light than average.
• adv. In a firm or secure manner, securely; in such a way as not to be moved.
• adv. (of sleeping) Deeply or soundly.
• adv. Immediately following in place or time; close, very near.
• adv. Quickly, with great speed; within a short time.
• adv. Ahead of the correct time or schedule.
• n. (Britain, rail transport) A train that calls at only some stations it passes between its origin and destination,…
• interj. (archery) Short for "stand fast", a warning not to pass between the arrow and the target.
• v. (intransitive) To restrict one’s personal consumption, generally of food, but sometimes other things,…
• n. The act or practice of abstaining from food or of eating very little food.
• n. The period of time during which one abstains from or eats very little food.

greaseproof

• adj. Resistant to grease.
• v. (transitive) To make resistant to grease.

impermeable

• adj. impossible to permeate.
• adj. not allowing passage, especially of liquids; waterproof.

imperviable

• adj. impervious.

mothproof

• adj. Resistant to being eaten by moths.
• v. To apply odoriferous materials intended to repel moths from clothing.

proof

• n. (countable) An effort, process, or operation designed to establish or discover a fact or truth; an act…
• n. (uncountable) The degree of evidence which convinces the mind of any truth or fact, and produces belief;…
• n. The quality or state of having been proved or tried; firmness or hardness which resists impression, or…
• n. (obsolete) Experience of something.
• n. (uncountable, obsolete) Firmness of mind; stability not to be shaken.
• n. (countable, printing) A proof sheet; a trial impression, as from type, taken for correction or examination.
• n. (countable, logic, mathematics) A sequence of statements consisting of axioms, assumptions, statements…
• n. (countable, mathematics) A process for testing the accuracy of an operation performed. Compare prove,…
• n. (obsolete) Armour of excellent or tried quality, and deemed impenetrable; properly, armour of proof.
• n. (US) A measure of the alcohol content of liquor. Originally, in Britain, 100 proof was defined as 57.1%…
• adj. Used in proving or testing.
• adj. Firm or successful in resisting.
• adj. (of alcoholic liquors) Being of a certain standard as to alcohol content.
• v. (transitive, intransitive, colloquial) To proofread.
• v. (transitive) To make resistant, especially to water.
• v. (transitive, cooking) To allow to rise (of yeast-containing dough).
• v. (transitive, cooking) To test the activeness of (yeast).

resistant

• n. A person who resists; especially a member of a resistance movement.
• n. A thing which resists.
• adj. Which makes resistance or offers opposition.
• adj. Which is not affected or overcome by a disease, drug, chemical or atmospheric agent, extreme of temperature,…
• adj. (statistics) Not greatly influenced by individual members of a sample.

soundproof

• adj. Not allowing sound through.
• v. To make resistant to transmitting sound.