abate 

v. To become weaker; to decrease.

[The speaker waited until the applause had abated before continuing.]

unabated adj. Showing no sign of weakening;showing no decrease

[Representative Millet showed unabated enthusiasm for campaigning for the Senate seat, even though he had been twice defeated for that office.]

v. 1. To admit the existence of.

[Did the police officer acknowledge your right to remain silent?]

2. To express recognition or thanks for.

[The new Wimbledon singles champion raised her hand to acknowledge of the cheers of the crowd.]

acknowledged adj. Commomly accepted or recognized.

[Julia Child is an acknowledged expert on french cooking.]

n. 1. A person who acts or does business for another.

[The author's agent found a company to publish his latest mystery story.] 

2. Something that brings about a result.

[A new principal can be a powerful agent for change in a school.]

n. 1. The right to give orders, make desicions, or take action.

[Only the Congress of the United States has the authority to declare war.]

2. An expert source of information.

[The researcher Jane Goodall is a world authority on chimpanzees.]

authorities n. A group of people who have the right to enforce laws.

[The authorities closed down the restauraunt because it did not meet the proper standards for cleanliness.] 

v. To ruin or destroy completely.

[Farmers in the Midwest fear that lack of rain will devastate the wheat crop.]

devastating adj.  Causing destruction.

[A devastating hurricane destroyed hundreds of homes in Southrn Florida.]

devastation n. Great destruction.

[The earthquake in Japan created a massive devastation.]

n. The rapid spreading of a disease to many people at one time.

[The flu epidemic of 1918 killed over twenty million people in the northern hemisphere.] 

adj. Spreading rapidly as a disease over a wide area.

[AIDS became epidemic in central Africa in the 1980s.]

n. A number that is not exact; a careful guess.

[The mechanic's estimate for repairing the car is $1000.]

v. To figure out roughly; to make an approximate calculation.

[We estimate that it will take us an hour to drive to the airport.]

v. To force out of property by taking legal action.

[The landlord threatened to evict the tenants for not paying the rent.] 

adj. Not favoring one side more than anothe; fair.

[A judge should be impartial in the courtroom.] 

adj. Hard working; not lazy.

[The more industrious in the clothing factory were rewarded with pay raises at the end of the year.]

v.  To make very angry.

[Cruelty to animals infuriates me.] 

irrelevant

adj. Having nothing to do with the subject.

[The candidate's personal wealth is irrelevant  to our discussion about his qualifications for the job.]

adj. Exact; accurate.

[Do you know the precise time that your plane arrives?]

precision noun. Exactness.

[An eye surgeon's work requires precision.]

n. Something fake or flase.

[Their offer to make us rich turned out to be a sham.]

adj. Not genuine;fake.

[Although he tried to appear sorry, his sham apology fooled no one.]

v. To pretend.

[We shammed illness so we could stay home] 

n. A long, slow, and difficult journey.

[The hikers were exhausted after their trek over the mountain.]

v.To travel slowly and with difficulty.

[Sam trekked ten miles into town after his car broke down.]