noun /ɪˈluʒn/
something that seems to exist but in fact does not, or seems to be something that it is not

Synonyms: deception, misperception, impression

Antonyms: reality

Mirrors in a room often give an illusion of space.

Adjective /ˈwɛːri/
feeling or showing caution about possible dangers or problems

Synonyms: cautious, careful, circumspect, on one's guard, chary, alert

Antonyms: unwary, inattentive, trustful

dogs which have been mistreated often remain very wary of strangers

Noun /pəˈrɪf(ə)ri/
the outer limits or edge of an area or object

Synonyms: edge, outer edge, margin, fringe, boundary, border

Antonyms: centre, middle, heart

new buildings on the periphery of the hospital site

Verb /bɪˈtreɪ/
expose (one's country, a group, or a person) to danger by treacherously giving information to an enemy

Synonyms: break one's promise to, be disloyal to, be unfaithful to, break faith with, play someone false, fail

Antonyms: be loyal to, conceal, hide

a double agent who betrayed some 400 British and French agents to the Germans

Adjective /ˈiːɡə/
strongly wanting to do or have something

Synonyms: keen, enthusiastic, avid, fervent, fervid, ardent

Antonyms: apathetic, uninterested

the man was eager to please

Adjective /ˈɡʌləb(ə)l/
easily persuaded to believe something; credulous

Synonyms: credulous, over-trusting, over-trustful, trustful, easily deceived, easily led

Antonyms: cynical, suspicious

an attempt to persuade a gullible public to spend their money

Verb /ˈbaf(ə)l/
totally bewilder or perplex

Synonyms: perplex, puzzle, bewilder, mystify, bemuse, confuse

Antonyms: enlighten, further

an unexplained occurrence that baffled everyone

Verb /bɪˈreɪt/
scold or criticize (someone) angrily

Synonyms: rebuke, reprimand, reproach, reprove, admonish, remonstrate with

Antonyms: praise

she berated herself for being fickle

Noun /ˈkɒntrakt/
a written or spoken agreement, especially one concerning employment, sales, or tenancy, that is intended to be enforceable by law

Synonyms: agreement, commitment, arrangement, settlement, undertaking, understanding

he has just signed a contract keeping him with the club

Adjective /ˈkɒmplɛks/
consisting of many different and connected parts

Synonyms: complicated, involved, intricate, convoluted, tangled, elaborate

Antonyms: simple, straightforward

a complex network of water channels

Adjective /ˈbrɪt(ə)l/
hard but liable to break easily

Synonyms: breakable, splintery, shatterable, fragile, frail, delicate

Antonyms: flexible, resilient, soft, relaxed, cool

her bones became fragile and brittle

Verb /strʌɪd/
walk with long, decisive steps in a specified direction

Synonyms: march, stalk, pace, tread, step, walk

he strode across the road

Adjective /ˈʌɪd(ə)l/
(of a person) avoiding work; lazy

Synonyms: lazy, indolent, slothful, work-shy, shiftless, loafing

Antonyms: industrious, employed, working, busy, full, serious

idle students

Verb /ˈʃʌf(ə)l/
walk by dragging one's feet along or without lifting them fully from the ground

Synonyms: shamble, drag one's feet, stumble, lumber, scrape, drag

I stepped into my skis and shuffled to the edge of the steep slope

Adjective /ˈpɑːʃ(ə)l/
existing only in part; incomplete

Synonyms: incomplete, limited, qualified, restricted, imperfect, fragmentary

Antonyms: complete, total, whole, unbiased, impartial, disinterested

a question to which we have only partial answers

Adjective /ɪnˈkluːsɪv/
including all the services or items normally expected or required

Synonyms: all-in, all-inclusive, with everything included, comprehensive, in toto, including

Antonyms: exclusive, excluding

menus stating fully inclusive prices

Adjective /ˈmʌɪzəli/
of or characteristic of a miser

Synonyms: niggardly, parsimonious, close-fisted, meagre, inadequate, paltry

Antonyms: spendthrift, generous, lavish, huge

his miserly great-uncle proved to be worth nearly £1 million

Verb /kənˈsiːl/
not allow to be seen; hide

Synonyms: hide, keep out of sight, keep hidden, secrete, tuck away, hide

Antonyms: reveal, expose, show, disclose, confess

a line of sand dunes concealed the distant sea

Adjective /ˈdʒɛnjʊɪn/
truly what something is said to be; authentic

Synonyms: authentic, real, actual, original, bona fide, true

Antonyms: bogus, fake, bogus, insincere

genuine 24-carat gold

Adjective /spɑːs/
thinly dispersed or scattered

Synonyms: scanty, scant, scattered, thinly distributed, scarce, infrequent

Antonyms: abundant, plentiful, thick

areas of sparse population