SOAPBOX

dais, podium, pulpit, rostrum, ambo, stump, soapbox

(noun) a platform raised above the surrounding level to give prominence to the person on it

soapbox

(noun) a crate for packing soap

Source: WordNet® 3.1

Etymology

Noun

soapbox (plural soapboxes)

(literally) A crate for packing soap.

(figuratively) Any physical or media platform which gives prominence to the person on it and the views they espouse.

(figuratively) A talk about one's pet topic (or the topic itself), especially when only tangentially relevant to an ongoing discussion.

A soapbox car.

Verb

soapbox (third-person singular simple present soapboxes, present participle soapboxing, simple past and past participle soapboxed)

To give a speech from (or as if from) a soapbox.

Source: Wiktionary