investment vs arbitrage

investment and arbitrage both are nouns.

Word	Noun	Adjective	Verb	Adverb
investment	Yes	No	No	No
arbitrage	Yes	No	Yes	No

As nouns, arbitrage is a hyponym of investment; that is, arbitrage is a word with a more specific, narrower meaning than investment:

investment: the act of investing; laying out money or capital in an enterprise with the expectation of profit
arbitrage: a kind of hedged investment meant to capture slight differences in price; when there is a difference in the price of something on two different markets the arbitrageur simultaneously buys at the lower price and sells at the higher price

Other hyponyms of investment include foreign direct investment, leverage, leveraging, long-term investment.

investment (noun)	arbitrage (noun)
the act of investing; laying out money or capital in an enterprise with the expectation of profit	a kind of hedged investment meant to capture slight differences in price; when there is a difference in the price of something on two different markets the arbitrageur simultaneously buys at the lower price and sells at the higher price
the act of putting on robes or vestments
the ceremonial act of clothing someone in the insignia of an office; the formal promotion of a person to an office or rank
outer layer or covering of an organ or part or organism
the commitment of something other than money (time, energy, or effort) to a project with the expectation of some worthwhile result
money that is invested with an expectation of profit

investment (verb)	arbitrage (verb)
	practice arbitrage, as in the stock market