快適【かいてき】
pleasant, agreeable, comfortable
軽快【けいかい】
light (of movements), nimble, sprightly, springy, light-hearted, cheerful, buoyant, jaunty, casual (e.g. clothing), rhythmical (e.g. melody), taking a turn for the better (of an illness), receding of symptoms, recovery, convalescence
不快【ふかい】
displeasure, discomfort, unpleasantness, indisposition, ailment
不愉快【ふゆかい】
unpleasant, disagreeable, displeasing, uncomfortable, unhappy
快速【かいそく】
high speed, rapidity, rapid-service train (not as fast as express), rapid train
愉快【ゆかい】
pleasant, delightful, enjoyable, joyful, cheerful, amusing, happy
快晴【かいせい】
clear weather, cloudless weather, good weather
快い【こころよい】
pleasant, agreeable, comfortable, refreshing
快楽【かいらく】
pleasure, supreme pleasure obtained by freeing oneself from earthly desires
快活【かいかつ】
cheerful, lively, lighthearted