cosponsor

noun

co·​spon·​sor (ˌ)kō-ˈspän(t)-sər 

variants or co-sponsor

plural cosponsors or co-sponsors

: a joint sponsor

The senator was a cosponsor for both bills.

Michigan Tech Student Relay For Life is a participating cosponsor of this event.

—The Daily Mining Gazette

cosponsor transitive verb

or co-sponsor

cosponsored or co-sponsored; cosponsoring or co-sponsoring

This year Simpson is carrying on the legislative struggle without Mazzoli, who has declined to cosponsor the bill without support from the Democratic House leadership …

—George Russell

The following summer, Bingham returned to Machu Picchu with an expedition co-sponsored by the National Geographic Society.

—Duane Damon

cosponsorship

(ˌ)kō-ˈspän(t)-sər-ˌship 

noun

or co-sponsorship

Increasingly, large urban malls are being built with the co-sponsorship of city governments.

—Witold Rybczynski

Examples of cosponsor in a Sentence

Recent Examples on the Web

Defense & National Security The Big Story Absent Trump support, GOP leery of approving tougher Russian sanctions A bipartisan bill to place tough sanctions on Russia has more than 80 Senate cosponsors, but Senate Republicans are leery of putting it on the floor without President Trump’s approval. —Ellen Mitchell, The Hill, 30 May 2025

Several top Republican lawmakers and Noem attended the signing ceremony, as did Democratic Sen. John Fetterman of Pennsylvania, a cosponsor. —Will Weissert, Chicago Tribune, 29 Jan. 2025

The bill has seven cosponsors from California’s congressional delegation, including Rep. Lou Correa, D-Santa Ana. —Lillian Ashworth, Oc Register, 13 June 2025

The House version of the bill already has 130 cosponsors. —Time, 12 June 2025

Word History

First Known Use

1849, in the meaning defined above

Rhymes for cosponsor

• sponsor