The phrase "slightly tipsy" is correct and can be used in written English.
It means to be slightly drunk or feeling the effects of alcohol. Example: After two glasses of wine, I could feel myself getting slightly tipsy. This phrase can be used in any situation where someone is experiencing the effects of alcohol, but not to the point of being extremely drunk. It can also be used to describe someone who is not fully sober, but not completely drunk.
Slightly Tipsy Woman Standing on a Hill Outside the Club: You're VINCE VAUGHN!
I'm never happier than when I'm deliberately losing at table football to my slightly tipsy line manager.
Entourage is like an enthusiastic puppy, slightly tipsy on beer, humping on a stripper's leg, but desperate to please nonetheless.
The appeal is equal parts cynicism — the schadenfreude shots of the losers, the badly dressed, the (please, someone) slightly tipsy — and surprise.
It's hard to equate the messed-up drug addict of those years with the genial, if slightly tipsy man who sits opposite me.
"You're very aware of the time of year [at Christmas], and the noisy, sugared-up, slightly tipsy household," said Doctor Who writer Steven Moffat.
Later this afternoon, Bradley Wiggins will cycle through the Champs-Elysees and, ever-so-slightly tipsy on champagne, be crowned the first ever British winner of the Tour de France.
Though Delorean finished their set before 8pm, the crowd continued dancing for over an hour, squealing like slightly-tipsy children when enormous beach balls and balloons were released over the courtyard.
The host, mainly a beer drinker, found his Sherry a bit uninteresting, not so his guests, whobecame slightly more than tipsy.
— one sluiced with vodka and horseradish, the next with bourbon and bacon, the third with tequila and smoked roe, and you are all at once tipsy, slightly full and ready for a glass of cold beer.
These were worn in a slightly careless manner, over simple knits and sparkling evening sequins alike, and they made one think of a tipsy but well-dressed matron emerging from Cipriani as she hastily readjusts her clothes.
