Content has two meanings which are separated by pronunciation. When the stress is placed on the first syllable (con tent), content means materials inside a container or the ideas presented in a speech or written work. These are both nouns.
Content with the stress placed on the second syllable (cun tent), means to be happy or satisfied. It can be used as an adverb, adjective, verb, or noun. However, each of these forms has two variations (e.g., contently, contentedly, content, contented, contentment, and contentedness). One set comes from the French and the other from Latin, but both had their origins in the 15th century. Each are interchangeable and have the same meaning. Contentedly is used twice as much as contently. Contentment is used more than contentedness.
These spelling variations extend to the antonyms of each word (e.g., discontent, discontented, discontment, discontentedness).
She began as a Teacher’s Aide, then taught 3-4 year olds, was briefly the Acting Director of the center, and then contently took care of infants. [Marshall Independent]
The Spanish newspapers are already carrying analysis from Navas’ native Costa Rica, stating that he is biding his time and playing contentedly in the Copa del Rey because he expects Casillas to leave at the end of this season. [Herald Scotland]
From his late 30s, Robert’s life seemed to settle; he seemed to find a contentment. [The Australian]
The reality of this relapse, in a marriage that is slowly finding its way to contentedness, requires love, trust and courage from R and me, and I’m sure we have that. [The Guardian]