Though one speak a thousand useless words, better is one single word of meaning that brings peace when heard.

Sahassamapi ce vācā — though a thousand words: the number thousand opens the chapter bearing that name. It represents abundance, large quantity. A thousand useless words versus one essential word.

Anatthapadasaṃhitā — useless: words without benefit are those that do not lead to calm, understanding or liberation — however brilliant, erudite or entertaining they may be.

Ekaṃ atthapadaṃ seyyo — better is one single word of meaning: attha is benefit, meaning. One single truly beneficial word infinitely surpasses thousands of others.

Yaṃ sutvā upasammati — that brings peace when heard: the final criterion is not the authority of the speaker but the effect on the listener. The word of true meaning produces peace. This is the pragmatic criterion of the Dhamma.