jchristopher/searchwp-customizations.php

## searchwp-customizations.php
<?php

// Add Synonym to existing Synonyms in SearchWP.
add_filter( 'searchwp\synonyms', function( $synonyms, $args ) {
  $synonyms[] = [
    'sources'  => 'seo',
    'synonyms' => 'search engine optimization',
    'replace'  => false,
  ];

  return $synonyms;
}, 20, 2 );
	<?php

	// Add Synonym to existing Synonyms in SearchWP.
	add_filter( 'searchwp\synonyms', function( $synonyms, $args ) {
	$synonyms[] = [
	'sources' => 'seo',
	'synonyms' => 'search engine optimization',
	'replace' => false,
	];

	return $synonyms;
	}, 20, 2 );