be the last word

be the last word in (something)

To be the most modern or advanced version of something. It may not look like much, but I can assure you that this machine is the last word in neural imaging.
See also: last, word

be the last word

be the most fashionable or up-to-date.
1989 Life Thanks to a built-in microchip, Teddy Ruxpin became the last word in talking dolls.
See also: last, word