Use the american dictionary to search for available domains.

whois-dict-based.rb

#!/usr/bin/ruby

require 'whois'
require 'whois-parser'
require 'logger'

#
class WhoisDiscovery
  def initialize
    $stdout.sync = true
    @logger = Logger.new($stdout)
    File.open('/usr/share/dict/american-english', 'r').each_line do |word|
      word = word.strip
      next if word.include? "'"
      whois("#{word}.com")
    end
  end

  def whois(domain)
    @logger.info "> whois(#{domain})"
    parser = Whois::Client.new(timeout: 10).lookup(domain).parser
    available = parser.available?
    expires_on = parser.expires_on
    @logger.info "< whois(#{domain}, #{available}, #{expires_on})"
  rescue Timeout::Error, Whois::ConnectionError, Whois::ParserError
    @logger.debug "whois.lookup(#{domain}) failed"
  end
end

WhoisDiscovery.new