霹雳与雷霆有什么分别？(What's the difference between 霹雳 and 雷霆?) except for their other uses, such as 霹雳舞(breakdance) and their respective 成语, are they considered synonyms? they're both translated as
霹雳: thunderbolt
雷霆: thunderbolt

空中雷霆一响，就把孩子吓哭了 = The thunderbolt came from the sky, and frightened
the child into crying.


我听到了一声霹雳，随后天空突然开始下起了雨 = I heard a clap of thunder, and then it
suddenly began to rain
According to 汉典:
霹雳 (pīlì) mainly means thunderbolt as the atmospherical phenomenon.

又急又响的雷，是云与地面之间发生的强烈雷电现象
sudden and loud thunder, it's the strong lightning bolt occurring between the clouds and earth

雷霆 (léitíng) mainly means thunderclap, as the booming sound of the thunderbolt, and it's also used figuratively. In English that would be thunderous.

洪大而急发的雷声
booming and sudden thunder clap


比喻声威或怒气
describes metaphorically prestige or rage (thunderous, roaring)

 
In your examples, the two words look similar because of context:

空中雷霆一响

Here it's definitely thunderclap, reinforced by the presence of 响, denoting a sound. (The usage of “一 yī” follows the &quot;一 (yī) ～ 就 (jiù)&quot; structure, events in quick sequence). &quot;A thunderclap from the sky, ...&quot;.
Translating as &quot;The thunderbolt&quot; is not wrong, but that seems poetic license on the translator's part, which is fine, since the sentence can't be nicely translated word-for-word.

我听到了一声霹雳

Here 霹雳 is preceded by 一声, which works as a classifier / measure word, and results in &quot;one sound of thunderbolt&quot;. Therefore &quot;I heard a clap of thunder.&quot;