ex /eks/ noun [countable usually singular]
[Date: 1800-1900; Origin: ex-]
informal someone’s former wife, husband, girlfriend, or boyfriend:
I bumped into my ex in town.

[TahlilGaran] Dictionary of Contemporary English ▲

ex- /eks/ prefix
[Language: Latin; Origin: ex 'out of, from']
former and still living:
his ex-wife
an ex-England cricketer

[TahlilGaran] Dictionary of Contemporary English ▲

boyfriend a boy or man that you have a romantic relationship with, especially for a fairly long time:
Josh was my first boyfriend.
partner the person you are married to, or the person you are living with and having a sexual relationship with:
Sweden allows gay partners to receive many of the same benefits that married couples get.
Partners are also welcome.
fiancé the man whom a woman is going to marry:
Her fiancé was killed in the war.
lover someone who you have a sexual relationship with, without being married to them:
A few nights later, they became lovers.
ex informal a woman’s former husband or boyfriend:
Her ex has caused a lot of trouble for her.
old flame informal someone who was your boyfriend in the past:
In a box in the closet, I found love letters from one of her old flames.
man informal a woman’s husband or boyfriend:
She’ll always stand by her man.
sweetheart old-fashioned the person that you love:
They were childhood sweethearts.
beau old-fashioned a woman’s boyfriend or lover - a very old-fashioned use:
Does she have a beau?
toy boy informal humorous a young man who is having a sexual relationship with an older woman:
A woman with a toy boy gets a lot more disapproving looks than a man with a younger woman.
sugar daddy informal an older man who gives a younger woman presents and money in return for their company and often for sex:
I can imagine her cashing checks from some mysterious sugar daddy.
be going out with somebody if you are going out with a boy or man, you have him as your boyfriend:
She’s been going out with Jack for a couple of months.

[TahlilGaran] English Thesaurus ▲

girlfriend a girl or woman that you have a romantic relationship with, especially for a fairly long time:
Katherine was his first girlfriend.
partner the person you are married to, or the person you are living with and having a sexual relationship with:
He brought his partner along to the party.
old flame informal someone who was your girlfriend or boyfriend in the past:
I found a love letter from one of his old flames.
mistress a woman that a man has a sexual relationship with even though he is married to someone else. Often used when the man is famous or powerful:
The president had a mistress for many years.
lover someone who you have a sexual relationship with, but who you are not married to:
He was going to meet his secret lover.
fiancée the woman who a man is going to marry:
Rod plans to marry his fiancée later this year.
ex informal a man's former wife or girlfriend:
My ex looks after the children on Thursdays.
be going out with somebody if you are going out with a girl or woman, she is your girlfriend:
She's going out with a guy she met at work.

[TahlilGaran] English Thesaurus ▲

Ex.
Excluding. Examined. Exchange. Executed. Out of. Without

[TahlilGaran] Acronyms and Abbreviations Dictionary ▲