.....exhortative (Particle etc.) used in enjoining or encouraging an action by a group that includes the speaker: e.g. let or let's in Let's go.
'aptote' Obsolete term for a noun which, unlike others in the relevant language, is not inflected for case.
arhyzotonic Having the accent elsewhere than on the root.
atonic (Word, syllable, vowel) not accented.
Definitions from: The Concise Oxford Dictionary of Linguistics, Second edition, 2007
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