Sudden Advance is a term that can be used to describe a situation in which something advances quickly and unexpectedly. This term can be broken down into two words, 'DASH' and 'ONRUSH, ' both of which have four and six letters respectively. DASH is defined as a sudden, short movement forward, while ONRUSH is defined as a forceful or rapid advance. Together, these two words form the phrase Sudden Advance, which can be used to describe a situation in which something moves forward quickly and without warning.