(metallurgy, blacksmithing, literally) To strike a hot piece of metal, especially iron, with a mallet or other tool before it cools, while it is still hot enough to be shaped.

(idiomatic) To neglect helping when one’s time is needed most; to ignore the major problem at hand (whilst doing something less important); to be idle, inactive, or uninterested in a time of great need.

Alternative form of strike while the iron is hot

(idiomatic) To stop taking risks before one starts losing.

present participle of fiddle while Rome burns

simple past tense and past participle of fiddle while Rome burns

simple past tense and past participle of fiddle while Rome burns

Third-person singular simple present indicative form of fiddle while Rome burns

(colloquial) To leave at an opportune time or before adverse conditions arise.

(literally, agriculture) To make hay during favourable (dry) weather. / (idiomatic) To act while an opportunity exists; to take action while a situation is favorable.