"Major snub" refers to a significant or significant disregard or rejection of someone or something; often in a public or important context, where someone is intentionally overlooked or excluded. Full definition
Seen as one of last year's major snubs for his powerful role in Beasts of No Nation, Idris Elba might finally score his first nomination for romantic drama The Mountain Between Us. (theguardian.com)
As with the documentary category, the Academy previously released a foreign film shortlist in December, and at that time the omissions of films such as the widely praised Two Days, One Night, Winter Sleep (which won the Palme d'Or at Cannes last year), and Mommy were considered major snubs. (metacritic.com)
Granted, there were other major snubs involving potential Best Picture nominees in this category including «Carol,» «Room,» «The Hateful Eight,» «Bridge of Spies» and «Brooklyn,» but «Spotlight's» omission is truly puzzling. (awardscampaign.com)