banner (Noun) — Long strip of cloth or paper used for decoration or advertising.
banner (Noun) — A newspaper headline that runs across the full page.
banner (Noun) — Any distinctive flag.
banner (Noun) — A notional title or justification. ex. "They usually make their case under the banner of environmentalism"
banner (Noun) — An advertisement on a web page or on television taking the form of a graphic or animation above or alongside the main content.
banner (Adjective) — Unusually good; outstanding. ex. "a banner year for the company"