Change the word Event/Events globally on your calendar. This example uses Meeting/Meetings instead. Change the single and plural options below to whatever word you'd like to use.

functions.php

<?php

// Singular
add_filter( 'tribe_event_label_singular', 'event_display_name' );
function event_display_name() {
	return 'Meeting';
}
add_filter( 'tribe_event_label_singular_lowercase', 'event_display_name_lowercase' );
function event_display_name_lowercase() {
	return 'meeting';
}

// Plural
add_filter( 'tribe_event_label_plural', 'event_display_name_plural' );
function event_display_name_plural() {
	return 'Meetings';
}
add_filter( 'tribe_event_label_plural_lowercase', 'event_display_name_plural_lowercase' );
function event_display_name_plural_lowercase() {
	return 'meetings';
}