endarken

en- +‎ darken (see en- (“intensifying prefix”)), modelled on enlighten.[1]

• (General American) IPA^(key): /ɪnˈdaɾkɪn/
• (Received Pronunciation) IPA^(key): /ɪnˈdɑːkən/

endarken (third-person singular simple present endarkens, present participle endarkening, simple past and past participle endarkened)

1. (transitive, rare, chiefly literary) To render dark or darker.
   • John Strype

     Suffer not Satan to endarken your consciences; let brawlings cease, and let unity be seen.

2. (transitive, chiefly literary) To becloud, obscure, to obfuscate; to confound.

• (render dark) enlighten

• enranked, rankened