A Word Is Dead is a poem written by Emily Dickinson.

Just considering the title, the reader may expect the poem to deal with words and their life. They are probably living entities because the speaking voice uses the word "Dead".

The layout shows the composition consists of six lines arranged into two similar patterns: two tercets, that are stanzas of three lines each, separated by a full stop. It follows that the reader wants to know the reason of such structure.

Taking structure into a count, the reader has to read the text to find out content and later became aware of the functions of the two tercets in the economy of the poem.

The speaking voice reports common people's opinion about the life of a word once it is said. At the same time the speaker expresses his point-of-view on the matter discussed and asserts her strong opinion: words start living when said. 
There is no doubt structure helps meaning in that the two stanzas contain two different perspectives on the topic discussed.

Structure alone does not underline the personal conviction of the poetess: the alternation of passive and active form of verbs add to meaning. "It is said" in the first tercet find its correspondent expression in "I say" in the second one. There is no need to highlight how passivity and activity refer to opposite states of life and as a result the intelligent reader may well understand that meaning is the result of a contrast that manifest its strength through structure, verb form and last but not least syntax and semantic choices.
Word order plays a relevant role in the communicative function of the poem. Indeed the choice of two stressed words following one other adds strength to meaning and in particular brings strongly to surface poetess’ idea about words and their existence. At the same time the phrase "I say" immediately recalls "some say" of the previous line. This happens thanks to the use of alliterative sound that peck words together. In addiction one cannot but the mention the frequent occurrence of sound "s" in the whole text. It is a way to create sound parallelism between words and create cohesion between the two stanzas and of course between the two different points-of-view.
The life of words come to the forefront in the semantic choices made by the poetess. The percentage of words that mostly comes to mind and strikes the reader belongs to the semantic field of time. People and words as well live and have their existence in time. "When it is said", "just", "begins", "to live" and "that day" are all expression referring to time and the relationship people and words have with time. Interesting is to notice that all verb tenses are in the simple present and aspect, meaning that the poetess' intention is to make readers feel and think that what she is writing is always true. 
There is also an infinitive that is clearly connective with an expression that may be considered a key one (that day).