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English Words Starting With A

8,734 entries — pick a word to see its definition, pronunciation, and usage.

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Noun Verb Adjective Adverb Plural noun Combining form Verb (transitive)Verb (intransitive)Verb (ambitransitive)

anergy
nounC2
/ˈænədʒi/A state of immune unresponsiveness, where the immune system fails to respond to a specific antigen.
aneroid
adjectivenounC2
/ˈæn.ə.rɔɪd/Operating without fluid; specifically, a barometer that measures atmospheric pressure using a flexible metal box instead of liquid.
aneroid barograph
nounC2
/ˈæn.ə.rɔɪd ˈbær.ə.ɡrɑːf/A self-recording scientific instrument that measures and continuously charts atmospheric pressure changes using a flexible metal cell (aneroid mechanism) without liquids.
aneroid barometer
nounLow-frequency
/ˌæn.ə.rɔɪd bəˈrɒm.ɪ.tər/A portable barometer that measures atmospheric pressure using a sealed, partially evacuated metal chamber that flexes with pressure changes, moving a pointer on a dial, without using liquid.
aneroid capsule
nounLow
/ˈæn.ə.rɔɪd ˈkæp.sjuːl/A sealed, flexible metal chamber containing a partial vacuum, designed to expand or contract in response to changes in atmospheric pressure.
anesthesia
nounLow-Frequency Technical Term
/ˌæn.ɪsˈθiː.zi.ə/The state of being unable to feel pain, sensation, or awareness, typically induced by drugs for medical procedures.
anesthesimeter
nounVery Low
/ˌæn.əsˈθiːz.ɪ.miː.tə/A device used to measure and/or regulate the flow of anesthetic agents during medical procedures.
anesthesiologist
nounC1/C2
/ˌæn.ɪsˌθiː.ziˈɒl.ə.dʒɪst/A medical doctor specializing in administering anesthesia and managing patient care before, during, and after surgery.
anesthesiology
nounC2
/ˌæn.ɪsˌθiː.ziˈɒl.ə.dʒi/The medical specialty dealing with the administration of drugs or other agents that cause insensitivity to pain, especially during surgery.
anesthetic
adjectivenounC1
/ˌæn.əsˈθet.ɪk/A substance used to induce insensitivity to pain during medical procedures, typically causing unconsciousness or localized numbness.
anesthetist
nounLow
/əˈniːs.θə.tɪst/A medical specialist, especially a nurse, trained to administer anaesthetics and monitor patients under anaesthesia.
anesthetize
verb-transitiveLow-Frequency
/əˈniːsθəˌtaɪz/To administer an anesthetic substance to someone, causing loss of sensation or consciousness, especially for a medical procedure.
anestrus
nounC2 / Very low frequency
/æˈniːstrəs/A period of sexual quiescence between cycles of estrus in female mammals, during which ovulation does not occur.
anethole
nounRare / Technical
/ˈæn.ɪ.θəʊl/A naturally occurring organic compound responsible for the characteristic taste and aroma of anise and fennel.
aneto
nounRare
/əˈneɪtəʊ/A specific proper noun referring to the highest peak in the Pyrenees mountain range.
aneuploid
adjectivenounLow
/ˈæn.jʊ.plɔɪd/Having an abnormal number of chromosomes in a cell.
aneuria
nounExtremely Rare / Obsolete
/eɪˈnjʊərɪə/The absence or deficiency of nervous energy; a condition of nervous exhaustion or weakness.
aneurin
nounRare / Technical
/əˈnaɪərɪn/An alternative name for vitamin B1, a nutrient essential for nerve function and carbohydrate metabolism.
aneurysm
nounC2
/ˈæn.jə.rɪ.zəm/A serious medical condition where an artery wall weakens and bulges outward, creating a balloon-like swelling.
anfinsen
nounExtremely Low
/ˈænfɪnsən/A proper noun, the surname of a notable scientist (Christian B. Anfinsen), most commonly associated with his foundational work in biochemistry and protein folding.

Showing 4721–4740 of 8734 words.