diff --git a/Library/Homebrew/cmd/install.rb b/Library/Homebrew/cmd/install.rb
index 2782b4d7df..a995f745e5 100644
--- a/Library/Homebrew/cmd/install.rb
+++ b/Library/Homebrew/cmd/install.rb
@@ -109,12 +109,13 @@ module Homebrew
 
     Homebrew::CLI::Parser.new do
       usage_banner <<~EOS
-        `install` [<options>] <formula>
+        `install` [<options>] <formula>|<cask>
 
-        Install <formula>. Additional options specific to <formula> may be appended to the command.
+        Install a <formula> or <cask>. Additional options specific to a <formula> may be
+        appended to the command.
 
-        Unless `HOMEBREW_NO_INSTALL_CLEANUP` is set, `brew cleanup` will then be run for the
-        installed formulae or, every 30 days, for all formulae.
+        Unless `HOMEBREW_NO_INSTALL_CLEANUP` is set, `brew cleanup` will then be run for
+        the installed formulae or, every 30 days, for all formulae.
       EOS
       switch "-d", "--debug",
              description: "If brewing fails, open an interactive debugging session with access to IRB "\
@@ -139,7 +140,7 @@ module Homebrew
       end
 
       formula_options
-      min_named :formula
+      min_named 1
     end
   end
 
diff --git a/docs/Manpage.md b/docs/Manpage.md
index 92fe5a90fd..94d6df25b8 100644
--- a/docs/Manpage.md
+++ b/docs/Manpage.md
@@ -304,12 +304,13 @@ If *`formula`* is provided, show summary of information about *`formula`*.
 * `-v`, `--verbose`:
   Show more verbose analytics data for *`formula`*.
 
-### `install` [*`options`*] *`formula`*
+### `install` [*`options`*] *`formula`*|*`cask`*
 
-Install *`formula`*. Additional options specific to *`formula`* may be appended to the command.
+Install a *`formula`* or *`cask`*. Additional options specific to a *`formula`* may be
+appended to the command.
 
-Unless `HOMEBREW_NO_INSTALL_CLEANUP` is set, `brew cleanup` will then be run for the
-installed formulae or, every 30 days, for all formulae.
+Unless `HOMEBREW_NO_INSTALL_CLEANUP` is set, `brew cleanup` will then be run for
+the installed formulae or, every 30 days, for all formulae.
 
 * `-d`, `--debug`:
   If brewing fails, open an interactive debugging session with access to IRB or a shell inside the temporary build directory.
diff --git a/manpages/brew.1 b/manpages/brew.1
index 2140c06953..4ccb2bd5ed 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -445,8 +445,8 @@ Print JSON of all available formulae\.
 \fB\-v\fR, \fB\-\-verbose\fR
 Show more verbose analytics data for \fIformula\fR\.
 .
-.SS "\fBinstall\fR [\fIoptions\fR] \fIformula\fR"
-Install \fIformula\fR\. Additional options specific to \fIformula\fR may be appended to the command\.
+.SS "\fBinstall\fR [\fIoptions\fR] \fIformula\fR|\fIcask\fR"
+Install a \fIformula\fR or \fIcask\fR\. Additional options specific to a \fIformula\fR may be appended to the command\.
 .
 .P
 Unless \fBHOMEBREW_NO_INSTALL_CLEANUP\fR is set, \fBbrew cleanup\fR will then be run for the installed formulae or, every 30 days, for all formulae\.