Definition of a
(Entry 1 of 13)
1a
: the 1st letter of the English alphabet
b
: a graphic representation of this letter
c
: a speech counterpart of orthographic a
2
: the sixth tone of a C-major scale
3
: a graphic device for reproducing the letter a
4
: one designated a especially as the first in order or class
5a
: a grade rating a student's work as superior in quality
b
: one graded or rated with an A
6
: something shaped like the letter A
7
capitalized
: the one of the four ABO blood groups characterized by the presence of antigens designated by the letter A and by the presence of antibodies against the antigens present in the B blood group
Definition of a (Entry 2 of 13)
1
—used as a function word before singular nouns when the referent is unspecified a man overboard and before number collectives and some numbers a dozen
2
: the same
birds of a feather swords all of a length
3a
—used as a function word before a singular noun followed by a restrictive modifier a man who was here yesterday
b
: any
a person who is sick can't work
c
—used as a function word before a mass noun to denote a particular type or instance a bronze made in ancient times
d
—used as a function word before a proper noun representing an example or type the attractions of a Boston or a Cleveland
e
—used as a function word before a proper noun to indicate limited knowledge about the referent a Mr. Smith called to inquire about the job
f
—used as a function word before a proper noun to distinguish the condition of the referent from a usual, former, or hypothetical condition a triumphant Ms. Jones greeted her supporters
g
—used before the name of a day of the week to refer to one occurrence of it Christmas falls on a Tuesday this year.
h
—used before the name of a person (such as a famous artist) when the name is being used to refer to something (such as a painting) created by that person Her violin is a Stradivarius.
i
—used before a family name to show that someone is a member of that family To be a Kennedy is to lead two lives …— Margaret Carlson
4
—used as a function word with nouns to form adverbial phrases of quantity, amount, or degree felt a bit tired
Definition of a (Entry 3 of 13)
\ ə \
Definition of a (Entry 4 of 13)
: of
—often attached to the preceding word kindalotta
a
verbDefinition of a (Entry 5 of 13)
archaic
: have
I might a had husbands afore now— John Bunyan
Definition of a (Entry 6 of 13)
1
absent
2
acceleration
3
acre
4
adult
5
alto
6
chemistry
amorphous
—usually used in combination a-Si
7
anode
8
answer
9
ante
10
anterior
11
are
12
area
13
atto-
14
author
a-
prefix (1)
\ ə \
Definition of a- (Entry 7 of 13)
1
: on : in : at
abed
2
: in (such) a state or condition
afire
3
: in (such) a manner
aloud
4
: in the act or process of
gone a-hunting atingle
a-
prefix (2)
\ (ˈ)ā also (ˈ)a or (ˈ)ä \
variants:
or an- \
(ˈ)an
\
Definition of a- (Entry 8 of 13)
: not : without
asexual
—a- before consonants other than h and sometimes even before h, an- before vowels and usually before h achromaticahistoricalanastigmaticanhydrous
-a-
combining formDefinition of -a- (Entry 9 of 13)
: replacing carbon especially in a ring
aza-
-a
noun suffix
\ ə \
Definition of -a (Entry 10 of 13)
: oxide
silica
Definition of A (Entry 11 of 13)
1
ace
2
adenine
3
ampere
A
symbolDefinition of A (Entry 12 of 13)
argon
Definition of Å (Entry 13 of 13)
angstrom
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Time Traveler for a
The first known use of a was before the 12th century
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