Crawling and indexing are two different things and it is generally considered incorrect in the SEO industry.
Crawling means Googlebot sees and analyzes all the content/code on the page.
Indexing means that the page is eligible to show in Google's search results. They are not mutually inclusive.
Crawling is the process or reading through your webpage source by search engine spiders. They provide a cache certificate after a successful crawl. Indexing is updating the cached webpages in search engine database. Indexed webpages are now ready for search engine rankings.