Sentence:  Because I'm <WSD>happy</WSD> / Clap along if you know what happiness is to you / Because I'm <WSD>happy</WSD> / Clap along if you feel like that's what you wanna do 
Meaning of the word marked with <WSD> tags:  Having a feeling arising from a consciousness of well-being or of enjoyment; enjoying good of any kind, such as comfort, peace, or tranquillity; blissful, contented, joyous.