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Spell Bee Word: efficacy


Basic Details

Word: Efficacy

Part of Speech: Noun

Meaning: How well something works to give the result it is meant to give, used especially for medicines and treatments.

Synonyms: effectiveness, power

Antonyms: ineffectiveness

How to Spell Efficacy

Syllables: ef - fi - ca - cy

Tricky part: It starts with a double f. The first c says k and the second c says s, but both are written c, never k or s.

Watch out for: eficacy, efficasy, effecacy

Memory tip: Begin like efficient, with eff and an i. Then write c-a-c-y, with no s anywhere.

Usage Examples

Example 1: Scientists tested the efficacy of the new vaccine on thousands of volunteers.

Example 2: Nani was surprised by the efficacy of the cough syrup; she felt better in a day.

Example 3: Farmers want proof of a fertiliser's efficacy before they buy it.

Fun Fact

Efficacy comes from the Latin verb efficere, to bring about, which also gave English the words effect and efficient.

Practise the CREST Way

Word Connection

Choose the synonym of the word:

efficacy

a) weakness
b) effectiveness
c) delay
d) failure

Show answer

b) effectiveness. Efficacy is about how well something works, which is what effectiveness means too.

Word Cookie

Insert the correct pair of letters to form a word:

eff_ca_y

a) e, c
b) i, c
c) a, s
d) i, s

Show answer

b) i, c. Eff is followed by i, as in efficient, and the last gap is another c.

Spell-o-Spell

Choose the correctly spelt word:

a) efficacy
b) perscription
c) dosege
d) antibiotec

Show answer

a) efficacy. Prescription, antibiotic and dosage all show a slip that doctors would spot at once.

Multiple Choice Questions

1. A doctor talks about the efficacy of a medicine. She means ____.

a) how much it costs
b) how well it works
c) what colour it is
d) how it tastes

Show answer

b) how well it works

2. Before a new medicine is sold, its efficacy is checked through ____.

a) a television advert
b) careful trials
c) a lucky draw
d) a spelling test

Show answer

b) careful trials

Associated Words

luggagehorrifyingirritablejoystickforward
sovereignbookkeeperillustrationquotationapproximate

Next steps

How to participate in CREST International Spell Bee

The CREST International Spell Bee (CSB) is conducted in two editions – CREST International Spell Bee - Summer (CSB) and CREST International Spell Bee - Winter (CSBW) – giving students across the globe an opportunity to showcase and enhance their spelling proficiency. Designed for young learners from Senior KG to Class 8, the competition focuses on word-building, pronunciation, and vocabulary enrichment, helping students develop strong linguistic skills.

Steps to Participate:

Step 1: Visit the registration page and complete the registration with your desired subject.

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Step 3: After login, go to dashboard and click on Book slot/Take Exam

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