cosignatory or co-signatory/kohʹsignət(ə)ri/ noun (pl -ies) (pl cosignatories)

• athletics
• athletic support
• at home
• -athon
• a thorn in somebody's flesh/side
• a thought
• athwart
• -atic
• -ation
• at issue
• at it
• -ative
• at knifepoint
• atlantes
• Atlantic
• Atlantic Standard Time
• at large
• atlas
• at last/at long last
• at least
• at leisure/at one's leisure
• at length
• at liberty
• at livery
• at loggerheads