wakeful adj.

"state of wakefulness," Old English -wacu (in nihtwacu "night watch"), related to watch (n.); and partly from Old Norse vaka "vigil, eve before a feast" (which is related to vaka "be awake" and cognate with Old High German wahta "watch, vigil," Middle Dutch wachten "to watch, guard"), from PIE root *weg- "to be strong, be lively." Meaning "a sitting up at night with a corpse" is attested from early 15c. (the verb in this sense is recorded from mid-13c.; as a noun lichwake is from late 14c.). The custom largely survived as an Irish activity. Wakeman (c. 1200), which survives as a surname, was Middle English for "watchman."

word-forming element attached to nouns (and in modern English to verb stems) and meaning "full of, having, characterized by," also "amount or volume contained" (handful, bellyful); from Old English -full, -ful, which is full (adj.) become a suffix by being coalesced with a preceding noun, but originally a separate word. Cognate with German -voll, Old Norse -fullr, Danish -fuld. Most English -ful adjectives at one time or another had both passive ("full of x") and active ("causing x; full of occasion for x") senses.

It is rare in Old English and Middle English, where full was much more commonly attached at the head of a word (for example Old English fulbrecan "to violate," fulslean "to kill outright," fulripod "mature;" Middle English had ful-comen "attain (a state), realize (a truth)," ful-lasting "durability," ful-thriven "complete, perfect," etc.).