icebreaker vs iceboat

icebreaker and iceboat both are nouns.

Word	Noun	Adjective	Verb	Adverb
icebreaker	Yes	No	No	No
iceboat	Yes	No	No	No

As nouns, icebreaker and iceboat are synonyms defined as:

icebreaker and iceboat: a ship with a reinforced bow to break up ice and keep channels open for navigation

icebreaker (noun)	iceboat (noun)
a beginning that relaxes a tense or formal atmosphere	a ship with a reinforced bow to break up ice and keep channels open for navigation
a ship with a reinforced bow to break up ice and keep channels open for navigation	a sailing vessel with runners and a cross-shaped frame; suitable for traveling over ice