re = /^(?:[\w:\-() ]+)$/m
str = 'Description: Corsican
Description: Cree
Description: Czech
Description: Church Slavic
Description: Church Slavonic
Description: Old Bulgarian
Description: Old Church Slavonic
Description: Old Slavonic
Description: Chuvash
Description: Welsh
Description: Danish
Description: German
Description: Dhivehi
Description: Divehi
Description: Maldivian
Description: Dzongkha
Description: Ewe
Description: Modern Greek (1453-)
Description: English
Description: Esperanto
Description: Spanish
Description: Castilian
Description: Estonian
Description: Basque
Description: Persian'
subst = ''
result = str.gsub(re, subst)
# Print the result of the substitution
puts result
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html