参加【さんか】
participation, joining, entry
加える【くわえる】
to add, to add up, to sum up, to append, to annex, to increase, to gather (e.g. speed), to pick up, to include, to count in, to let join, to inflict (damage), to deal, to give
加減【かげん】
degree, extent, amount, balance, state, condition, (health) condition, state of health, adjustment, moderation, regulation, addition and subtraction, slight sign of ..., slight state of ..., just right for ...
追加【ついか】
addition, supplement, appending, appendix
加わる【くわわる】
to be added to, to be appended, to join in (e.g. a group of friends), to participate, to increase (e.g. heat), to gain in (e.g. influence), to grow, to gather (speed), to be applied (e.g. heat, pressure), to be exerted
加工【かこう】
manufacturing, processing, treatment, machining
加速【かそく】
acceleration, speeding up
参加者【さんかしゃ】
participant, entrant, player, competitor
加護【かご】
divine protection
増加【ぞうか】
increase, rise, growth, addition, increment
いい加減【いいかげん】
irresponsible, perfunctory, careless, lukewarm, half-baked, halfhearted, vague, (already) enough, considerably, quite, rather, pretty
手加減【てかげん】
measuring by feel, adjusting by feel, doing by feel, knack, skill, adapting to the situation (one's strength, strictness, etc.), making allowances, using discretion, going easy (on someone)
加盟【かめい】
joining (an association, agreement, etc.), participation, affiliation, accession
加入【かにゅう】
joining (a club, organization, etc.), becoming a member, entry, admission, subscription, affiliation, signing (e.g. a treaty), taking out (insurance)
付加【ふか】
addition, annexation, appendage
加害者【かがいしゃ】
perpetrator, wrong-doer, aggressor, assailant, offender
添加【てんか】
addition, annexing
付け加える【つけくわえる】
to add (one thing to another), to add (a few more words, an explanation, etc.)
倍加【ばいか】
doubling, marked increase, multiplying, redoubling
加点【かてん】
adding points, addition of marks and symbols to a classical Chinese text to aid reading in Japanese