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ThesaurusAntonymsRelated WordsSynonymsLegend: - one year of age
young, immature - (used of living things especially persons) in an early period of life or development or growth; "young people"


(wan) noun
1. the number or figure 1. One and one is two (1 + 1 = 2).
2. the age of 1. Babies start to talk at one.
1. a single person or thing. She's the one I like the best; I'll buy the red one.
2. anyone; any person. One can see the city from here.
1. 1 in number. one person; He took one book.
2. aged 1. The baby will be one tomorrow.
3. of the same opinion etc. We are one in our love of freedom.
having one (of something). a one-legged man.
oneˈself pronoun
1. used as the object of a verb, the subject of which is one. One should wash oneself every morning.
2. used in emphasis. One always has to do these things oneself.
one-night ˈstand noun
(slang) a one-night sex partner; sexual intercourse with a one-night partner.
one-ˈoff noun, adjective
(something) made, intended etc for one occasion only. It's just a one-off arrangement.
one-parent ˈfamily noun
(also single parent family) a family with only a mother or a father to look after the children.
one-ˈsided adjective
1. with one person or side having a great advantage over the other. a one-sided contest.
2. representing only one aspect of a subject. a one-sided discussion.
one-ˈway adjective
1. in which traffic can move in one direction only. a one-way street.
2. (especially American) valid for travel in one direction only. a one-way ticket.
one-year-old noun
a person or animal that is one year old.
(of a person, animal or thing) that is one year old.
all one
just the same. It's all one to me what she does.
be one up on (a person)
to have an advantage over (someone). We brought out a book on this before our rivals so we're one up on them.
not be oneself
to look or feel ill, anxious etc. I'd better go home – I'm not myself today.
one and all
all (of a group). This was agreed by one and all.
one another
used as the object of a verb when an action takes place between people etc. They hit one another.
one by one
(of a number of people, things etc) one after the other. He examined all the vases one by one.
one or two
a few. I don't want a lot of nuts – I'll just take one or two.

one of is followed by a plural noun or pronoun, but takes a singular verb: One of the girls works as a hairdresser ; One of them is ill .
References in classic literature ?
Not only Princess Mary, who had been won by his gentleness with the pilgrims, gave him her most radiant looks, but even the one-year-old "Prince Nicholas" (as his grandfather called him) smiled at Pierre and let himself be taken in his arms, and Michael Ivanovich and Mademoiselle Bourienne looked at him with pleasant smiles when he talked to the old prince.
A ONE-year-old child with head injuries was flown to hospital after a fall in Almondbury.
Summary: Dhar (Madhya Pradesh) [India] February 9 (ANI): In a shocking incident, a mother killed her one-year-old daughter by slitting her throat with a sharp weapon in Madhya Pradesh's Dhar.
Muscat: Bollywood stars Kareena Kapoor Khan and her husband Saif Ali Khan have enrolled their one-year-old son Taimur Ali Khan in a gym, reported various Indian media outlets.
The research revealed that in the West Midlands the average wages of those with a one-year-old child rose by 14 per cent in cash terms - although pay is still falling in real terms - between 2008 and 2016.
Lisa Brown, 35, said her one-year-old niece Bonnie bumped her head and had a badly bruised lip when their car rammed into the back of another.
A VIOLENT bully who beat his partner while she cradled their one-year-old baby has avoided jail.
also, identified as five-year-old Ali Hamza, two-year-old Muzamil and one-year-old Maria.
Dito, one-year-old, three months old, nire-rape pinapatay, anak ka ng-tapos sabihin nila huwag iyang death penalty kasi inhuman?
Summary: One-year-old boy found dead in bathroom at home in Sharjah Industrial Area
The Rolling Stones guitar legend, 72, helped one-year-old Ray with the artwork during a break on the band's South American tour.
Angela Cockburn, 49, died along with husband David, 48, daughters Bethany, 18, and Carley Ann, 21, and one-year-old granddaughter Lacie Jade Stephenson, when their Nissan Primera was involved in a head-on collision with an HGV in April 2013 on the A18 in Lincolnshire.