bid vs underbid

bid is a noun but underbid is not a noun.

Word	Noun	Adjective	Verb	Adverb
bid	Yes	No	Yes	No
underbid	No	No	Yes	No

As verbs, underbid is a hyponym of bid; that is, underbid is a word with a more specific, narrower meaning than bid:

Other hyponyms of bid include by-bid, subscribe, overbid, outbid.

As verbs, underbid is a hyponym of bid; that is, underbid is a word with a more specific, narrower meaning than bid:

bid: make a demand, as for a card or a suit or a show of hands
underbid: bid (a hand of cards) at less than the strength of the hand warrants

Other hyponyms of bid include raise, double, outcall, outbid, overbid, preempt.

bid (noun)	underbid (noun)
an attempt to get something
a formal proposal to buy at a specified price
(bridge) the number of tricks a bridge player is willing to contract to make
an authoritative direction or instruction to do something

bid (verb)	underbid (verb)
ask someone in a friendly way to do something	bid too low
invoke upon	bid lower than a competing bidder
ask for or request earnestly	bid (a hand of cards) at less than the strength of the hand warrants
propose a payment
make a demand, as for a card or a suit or a show of hands
make a serious effort to attain something