language vs dictation

language and dictation both are nouns.

Word	Noun	Adjective	Verb	Adverb
language	Yes	No	No	No
dictation	Yes	No	No	No

As nouns, dictation is a hyponym of language; that is, dictation is a word with a more specific, narrower meaning than language:

language (noun)	dictation (noun)
the mental faculty or power of vocal communication	speech intended for reproduction in writing
the cognitive processes involved in producing and understanding linguistic communication	an authoritative direction or instruction to do something
a systematic means of communicating by the use of sounds or conventional symbols	matter that has been dictated and transcribed; a dictated passage
(language) communication by word of mouth
the text of a popular song or musical-comedy number
a system of words used to name things in a particular discipline