The phrase "a shared cup" is correct and usable in written English.
It can be used in contexts where you are referring to a cup that is used by multiple people, often symbolizing togetherness or communal experience.
Example: "During the ceremony, we passed around a shared cup to symbolize our unity and friendship."
Alternatives: "a communal cup" or "a joint cup".
She turns next to picking pears a work so exhausting that stopping to rest, drinking warm water from a shared cup, leaning back against my sack...
Faced with suspicious or recalcitrant parents, their only weapon is reassurance: a gentle pat on the hand, a shared cup of tea, an offer to seek religious assurances from a pro-vaccine cleric.
Tripping enables travelers to safely connect with locals for travel tips, a shared cup of coffee or even a home stay.
A few weeks ago she shared cups of green tea with a reporter at the Atlantic Grill near Lincoln Center.
BERLIN — Two guitar players strummed and sang in Farsi as a stream of Afghans and Iranians knelt at the front of Trinity Lutheran Church, sipping wine from a shared Communion cup.
(urban female)" The idea of TB being transmitted through sharing cups is especially mentioned in the context of sharing cups when drinking alcohol.
Do not share cups, straws or other personal items.
To be fair to FIFA, for all its chicanery, it has kept with a long term vision of keeping the World Cup a shared geographical experience.
Niall Sloane, ITV director of sport said: "The excitement building on the eve of this summer's tournament in Brazil demonstrates how the World Cup offers a shared, collective experience for people across the UK.
Go out for a meal, stay in and cook a meal, share a cup of tea or coffee, or work on a project together where possible.
Mr. Mogwanja spoke with mothers and members of the national Wawa Wasi programme staff, and recognized efforts made in reducing anaemia and malnutrition through the use of multi-micronutrients known as 'Sprinkles.' He watched the children eat a breakfast of enriched rations, tasted the highly nutritious cereal called quinoa and shared a cup of milk with a young girl called Pamela.
