beneficial
The definition for beneficial is "Helpful." Used in a sentence: there is no doubt that eating vegetables is beneficial to one's health.
eulogy
The definition for eulogy is "Speech or writing in praise of deceased." Used in a sentence: Ernesto delivered a moving eulogy at his uncle's funeral.
exasperation
The definition for exasperation is "The state of being irritated." Used in a sentence: The longer Jorge waited in line at the ticket counter, the more his exasperation grew.
fidelity
The definition for fidelity is "State of being faithful." Used in a sentence: Unlike her fickle friend Benji, May Belle was known for her fidelity.
interminable
The definition for interminable is "Never ending, or seemingly endless." Used in a sentence: The impatient Zoe found the longwinded lecture interminable.