attenuate
v. US //əˈtɛnjuˌeɪt// at·ten·u·ate
The verb if first attested in 1530, the adjective in 1626; borrowed from Latin attenuātus, the perfect passive participle of attenuō (see -ate (verb-forming suffix) and -ate (adjective-forming suffix)), from ad- (“to, towards, at”) + tenuo (“to make thin”), itself from tenuis (“thin”) + -ō (verb-forming suffix).