The word eventide means "evening" or the end of the day, and it originates from the Old English word (æfen (meaning "even" or "evening") and tīd (meaning "time", "season", or "fixed hour").  

According to the Oxford English Dictionary (OED), the earliest known use of the noun eventide dates back to the Old English period (pre-1150).  It is an archaic or literary noun meaning "evening" or the end of the day.  It is documented across Middle English as realted forms like eventid, eventyde, and enetid.  

Eventide—the evening, dusk, or twilight—serves as a potent narrative device in storytelling, symbolizing transition, introspection, the winding down of struggle, and the passage of finite time.  

Key Symbolic and Structural Roles in Storytelling:  
Transition and Liminality: Marking the threshold between day and night, eventide acts as a boundary state where rules shift, secrets emerge, or characters undergo psychological change.  
Introspection and Calm: As external demands fade with the light, the setting invites quiet reflection, honest conversations, or a reckoning with choices made during the harshness of the day. 
The Weight of Time: In narratives like short films or slow-burn dramas, twilight reminds characters of the finite nature of their moments, heightening urgency or forcing them to appreciate connection before darkness falls.  
Dignity in the Ordinary: In works such as Kent Haruf's novel Eventide, evening shadows and quiet domestic routines emphasize human resilience, community care, and simple endurance rather than loud, fast-paced spectacles. 

2 hours ago, drpaladin said:

If eventide is evening, would uneventide be morning?

1. A blend of "Uneventful" and "Eventide":
   • Uneventful means calm, quiet, or lacking any major incidents or excitement.
   • Eventide is an archaic or poetic word for evening (the latter part of the day as daylight fades).
   • If used creatively or poetically, "uneventide" would contextually translate to a quiet, calm, or unremarkable evening.

2. A typo for "Uneventful":
If you saw this in a sentence like "We had an uneventide afternoon," it is highly probable that the intended word was simply uneventful.

Just the facts:

EVENTIDE Definition & Meaning - Merriam-Webster

EVENTIDE Synonyms: 29 Similar and Opposite Words | Merriam-Webster Thesaurus

EVENTIDES Synonyms: 28 Similar and Opposite Words | Merriam-Webster Thesaurus