An abstract noun is a word for something that can't be experienced by any of the five physical senses; something that can't be seen, heard, smelled, tasted, or touched. An abstract noun is a word for something that is known, learned, thought, understood, or felt emotionally.
Some examples are:
Examples of abstract nouns are:
attitude
beauty
belief
calm
charm
cold
danger
disaster
ego
emotion
envy
fear
generosity
happiness
honor
ignorance
joy
kindness
stupidity
trust
An abstract noun is a word for something that can't be experienced by any of the five physical senses; something that can't be seen, heard, smelled, tasted, or touched. An abstract noun is a word for something that is known, learned, thought, understood, or felt emotionally.
Some examples are:
Examples of abstract nouns are:
attitude
beauty
belief
calm
charm
cold
danger
disaster
ego
emotion
envy
fear
generosity
happiness
honor
ignorance
joy
kindness
stupidity
trust
Some common nouns that start with 'i' are:ibexibisiceiconideaidentityidolimaginationimpinchinformationinkinninsightinspirationinventioninundationionirisironironyislandisolationissueisthmusitem
Examples of common abstract nouns:abilityboredomcharitydangeregofeargratitudehourintelligencejusticeknowledgelibertymoodneedopinionproblemquestionreasonseasontreasonurgevirtueworkyesterdayzeal
Some examples of 'quality of mind' nouns, also called abstract nouns, are:anxietybraveryconfidencedecisivenesseuphemismfungenerosityhappinessisolationjoyknowledgeluxurymemorynewsopinionpurposequestionreasonsorrowtroubleurgevaluewealthyearzeal
Some examples of abstract nouns for thoughts:thoughtsideasbeliefknowledgecuriositymemory
Some examples of abstract nouns ending in -ce are:absenceabstinenceabundanceavaricebenevolenceconfidencecowardicedalliancedeliverancedevianceeloquenceeminenceevidenceexcellencegracegrievancehindranceimpudenceinnocencemalicemalfeasancemenacenovicenuancenuisanceonceopulencepeacepenancepresencepriceprominenceprovidenceprudenceracereferencereliancesciencesentence (punishment)severancesourcestancetolerancetrancetrucetwicevariancevehemencevicevigilance
Some abstract nouns that end with the suffix 'dom' are:freedomwisdomboredomstardomSome abstract nouns that end with the suffix 'ship' are: friendshiprelationshipworshipcitizenship
Examples of abstract nouns that start with P are:partypatiencepeacepietypitypleasurepoliticspovertyprerequitsitproblemproofpunishment
Some example of abstract nouns that are principles are:democracydisciplinefreedomhonestyhonorintegrityjusticelibertyloyaltyvalor
If by 'invisible' you mean abstract nouns, words for things that can't be seen, heard, smelled, tasted, or touched, some examples are:attitudebeautycaredestinyeducationfriendshipgratitudehopeideajokekindnesslovemysteryneedopinionpeacequestreasonseasontrusturgevalueworryyearzeal
No, not all abstract nouns are uncountable. Some examples of countable abstract nouns are:an agreement; a number of agreementsan idea; a lot of ideasa lie; too many liesmy life; the lives of othersan opinion; a lot of opinionsa question; a few questionsThe most common abstract nouns that are uncountable are nouns for concepts and gerunds (verbal nouns). Some examples are:educationinformationknowledgeplayingrunningskating
Examples of positive feeling abstract nouns are:carecheerfulnessdelightfriendshiphappinesshopejoypleasurerelaxationsatisfactiontrustwelcome
Examples of abstract nouns for positive qualities are:braverycarefriendshiphappinesshonestyhopekindnessknowledgelovepatiencetruthunderstanding