Love:

A strong feeling of affection, tenderness, and attachment to another person or thing.

Etymology: From Middle English luf, from Old English lufu, from Proto-Germanic *lubō (“love”), from Proto-Indo-European *lewbʰ- (“to care, desire, love”).

Affection:

A fondness or tenderness towards someone or something.

Etymology: From Middle English affection, from Old French affection, from Latin affectio, affectiōnem (“desire, inclination, emotion”), from affectus (“desire, inclination, emotion”).

Fondness:

A feeling of deep love or affection for someone or something.

Etymology: From Middle English fondnes, from Old French fondnesse, from fond (“foolish, foolishly fond”), from Latin fundus (“bottom, foundation”).

Tenderness:

A feeling of gentleness, kindness, and sympathy.

Etymology: From Middle English tendren, from Old French tendre, from Latin tener (“soft, delicate”).

Attachment:

A strong feeling of affection and care for someone or something.

Etymology: From Middle English attechen, from Old French atacher (“to tie, bind, attach”), from Latin adtachō, adtacheō (“to fasten”).

Devotion:

Loyal and loving dedication to someone or something.

Etymology: From Middle English devocioun, from Old French devocion, from Latin devotiō, devotiōnem (“offering, dedication”), from devōtus (“devoted”).

Adoration:

The feeling of deep love and admiration for someone or something.

Etymology: From Middle English adoracioun, from Old French adoracion, from Latin adōrātiō (“adoration, worship”), from adōrāre (“to worship, adore”).

Passion:

A strong feeling of enthusiasm and excitement for something or someone.

Etymology: From Middle English passioun, from Old French passion, from Latin passiō, passiōnem (“suffering, enduring”), from passus (“suffered, endured”).

Compassion:

A feeling of sympathy and sorrow for the suffering of another, often accompanied by a desire to help.

Etymology: From Middle English compascioun, from Old French compassion, from Latin compassiō, compassiōnem (“feeling, emotion”), from compati (“to suffer with”).

Affinity:

A natural or instinctive feeling of connection or attraction to someone or something.

Etymology: From Middle English affinite, from Old French affinite, from Latin affinitās (“relationship, connection”).