Form 485BXT VANGUARD WORLD FUND

Explanatory Note

This Post-Effective Amendment No. 157 under the Securities Act of 1933, as amended (the “Securities Act”) (Amendment No. 157 under the Investment Company Act of 1940, as amended) to the registration statement on Form N-1A (the “Registration Statement”) of Vanguard World Fund (the “Trust”) is being filed pursuant to paragraph (b)(1)(iii) of Rule 485 under the Securities Act solely for the purpose of delaying, until November 11, 2018, the pending effective date of the Trust’s 150th Post-Effective Amendment. By way of further background:

• Post-Effective Amendment No. 154 was filed under Rule 485(b)(1)(iii) on September 14, 2018, for the sole purpose of extending to October 14, 2018, the then-pending effective date of Post-Effective Amendment No. 153.

• Post-Effective Amendment No. 153 was filed under Rule 485(b)(1)(iii) on August 17, 2018, for the sole purpose of extending to September 16, 2018, the then-pending effective date of Post-Effective Amendment No. 152.

• Post-Effective Amendment No. 152 was filed under Rule 485(b)(1)(iii) on July 20, 2018, for the sole purpose of extending to August 19, 2018, the then-pending effective date of Post-Effective Amendment No. 150.

• Post-Effective Amendment No. 150 was filed under Rule 485(a)(1) on May 2, 2018 for the purposes of: (1) changing the name of Vanguard Telecommunication Services Index Fund to Vanguard Communication Services Index Fund; (2) changing the benchmark index for Vanguard Telecommunication Services Index Fund; and (3) effecting a number of non-material editorial changes. Post-Effective Amendment No. 150 originally requested that the Amendment become effective on July 21, 2018, pursuant to the requirements of Rule 485(a)(1).

This Post-Effective Amendment No. 157 incorporates by reference the information contained in Parts A, B, and C of Post-Effective Amendment No. 150 to the Trust’s Registration Statement.