undergraduatish
Resembling or characteristic of an undergraduate.

undergrip
supinated grip

undergroomed
Inadequately groomed.

underground
Below the ground; below the surface of the Earth.
Hidden, furtive, secretive.
Of or relating to an art forms (such as music) or subculture that is outside the mainstream, especially one that is unofficial and hidden from the authorities.

underhaired
Lacking hair; balding.

underhead
A blockhead, or stupid person; a dunderhead.
The area directly below the head of something. (any sense)
The base of a railroad track.
direct costs.

underheads
plural of underhead

underhill
(of a road, track or other path) passing along the foot of a hill.

underhive
Located beneath a hive.

underhonest
Not entirely honest.

underhood
Beneath the hood of a vehicle.

underhoof
Under the hooves of an animal.

underhopped
Of beer: not hoppy enough.

underhorsed
Having too few horses.

underhouse
Located beneath a house.

underhoused
Inadequately housed.

underhydroxylated
insufficiently hydroxylated

underhyped
Receiving less hype than deserved

underided
Not derided.

underidentified
Insufficiently identified.

underilluminated
Insufficiently illuminated

underilluminating
That provides insufficient illumination

underimagined
Insufficiently imagined; betraying a lack of imagination.

underimpressed
Not strongly impressed; underwhelmed, disappointed.

underimproved
Having undergone insufficient improvement.

underinduced
Insufficiently induced

underinformative
Not informative enough.

underinformed
Given inadequate information.

underinspired
Lacking inspiration.

underinstrumented
Having inadequate instrumentation.

underinventive
insufficiently inventive

underinvestigated
insufficiently investigated

underinvolved
Insufficiently involved.

underisive
Not derisive.

underivable
That cannot be derived.

underivables
plural of underivable

underivatised
Alternative form of underivatized.

underivative
Not derivative.

underivatized
Not derivatized

underiveable
Rare form of underivable.

underived
not derived, not related.

underjawed
Having a heavy underjaw.

underkinds
plural of underkind

underknee
Below the knee.

underknown
Not known widely enough; of inadequate fame.

underlanguaged
Having inferior literacy skills.

underlayed
Misspelling of underlaid.

underlevelled
simple past and past participle of underlevel

underleveraged
Not adequately leveraged.

underlicensed
Having purchased fewer licences than are legally required.

underlieutenant
A subordinate lieutenant.

underlimbed
Having underdeveloped limbs.

underlinable
Capable of being underlined.

underlinked
Having underlying links; subtly interconnected.
Not linked strongly enough.

underlisted
Listed below (in the same document).

underlit
illuminated from beneath
poorly, or insufficiently illuminated

underloaded
Carrying a smaller load than normal or optimal

underloved
Insufficiently loved; neglected.

underluminous
Insufficiently luminous

undermarketed
Insufficiently marketed.

undermasculinized
Lacking the usual degree of masculinity.

undermassive
Of a star: having a smaller mass than is typical for its type.

undermasted
Having masts smaller than the usual size.
Having too few masts.

undermedicated
Given insufficient medication.

undermentioned
about to be specified or mentioned, especially in a document; following

undermet
Not fully met.

undermethylated
Insufficiently methylated

undermilled
Milled insufficiently, or less than usual.

underminable
Susceptible to being undermined.

undermineralized
Insufficiently mineralized.

undermodernized
Having undergone insufficient modernization.

undermodified
Insufficiently modified.

undermost
In the lowest position or state; bottom.

undermotivated
Not sufficiently motivated.

undermount
Mounted underneath something else.

undermountain
Beneath a mountain.

undermuscled
Inadequately muscled.

undermuscular
Synonym of undermuscled.

undermyelinated
Insufficiently myelinated

undernamed
Whose name appears underneath, or further down in a document.

undernatant
Synonym of surnatant.

undernatants
plural of undernatant

underneath
Below; in a place beneath.
On the underside or lower face.

underneaths
plural of underneath
genitalia

undernose
Located under the nose of the aircraft

undernoted
Of which a note is made underneath, or further down in a document.

undernutritional
Relating to undernutrition

undernutritious
Offering inadequate nutrition.

underoccupied
Not occupied enough, especially of a building with housing units.

underofficered
Having too few officers.

underogating
Not derogating.

underogatory
Not derogatory.

underorganized
Lacking organization.

underossified
Insufficiently ossified

underoxygenated
Having insufficient oxygen.
Lacking vitality; lackluster.

underpadded
Having padding underneath.
Having insufficient padding.

underpanted
Wearing underpants.

underparameterized
Insufficiently parameterized

underpasteurized
Not adequately pasteurized.

underpatronized
Not receiving enough clients or customers.

underpenetrated
Into which insufficient penetration has been achieved.

underpeopled
Short of people; underpopulated.

underperfused
Synonym of hypoperfused.

underpetticoated
Wearing an underpetticoat.

underphosphorylated
Insufficiently phosphorylated.

underpigmented
Inadequately pigmented.

underpitched
Given too low a pitch.

underplotted
Lacking in plot.

underpoliced
Inadequately policed.

underpolluted
Having relatively low pollution.

underpopulated
Having an insufficient population for economic viability

underpowered
simple past and past participle of underpower

underpredicted
predicted to be smaller than reality

underprenylated
simple past and past participle of underprenylate

underprepared
Not adequately prepared.

underpressurized
simple past and past participle of underpressurize

underpriced
Having a relatively or abnormally low price.
Underestimated.

underprioritised
Alternative spelling of underprioritized.

underprivileged
Deprived of the opportunities and advantages of others, usually through no fault of one's own.

underproduced
Having had inadequate time or effort spent on its production.

underproductive
Insufficiently productive.

underproficient
Inadequately proficient.

underprompt
Not prompt enough; tardy; delayed.

underprompter
A subordinate prompter.

underprosecuted
Of a crime: too infrequently prosecuted.

underprotected
simple past and past participle of underprotect

underprotective
Inadequately protective; not offering or providing sufficient protection.

underprovided
Provided to an inadequate extent.

underpublicized
Given inadequate publicity.

underpublished
Having few publications on the subject.

underpunctuated
Having insufficient punctuation.

underpunished
Insufficiently punished

underqualified
Lacking the suitable qualifications for a particular job.

underreactive
Insufficiently reactive; underreacting.

underread
To read below what is normal, usual, or expected, or with less competency, alertness, ability, etc.
To read to a lesser degree.

underrealized
Inadequately realized.

underrecompensed
Insufficiently recompensed.

underregulated
Insufficiently regulated.

underrehearsed
Insufficiently rehearsed

underreplicated
Insufficiently replicated

underreported
simple past and past participle of underreport

underrepresented
Having less than adequate or sufficient representation.

underresearched
Insufficiently researched.

underreserved
Having an inadequate reserve.

underresolved
Insufficiently resolved

underrespected
Insufficiently respected.

underresponsive
Insufficiently responsive.

underripe
Insufficiently ripe for harvesting or eating.

underripened
inadequately ripened

underroof
Beneath a roof.

underroot
Beneath the roots.

underrooted
Of a plant: having developed the roots insufficiently.

undersatisfied
Not satisfied enough.

undersaturated
Insufficiently saturated
(of igneous rock) Having minerals without free silica