25
The similar shape to a worldwide known symbol +, symbolized joining. ( +と類似の記号)
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( If you don't understand how to read this page, see here first )

the hand-shape-sign:
extend the index upward and open the thumb and the pinkie wide
symbolizing a cross shape. Face the palm side to the reader.
(3指と腕で十字を象って)

the hand-movement-sign:
draw the base shape starting from upper vertical line and connecting to the horizontal line
(縦の上から書きはじめる)

name: sha of sharp without extension of the vowel (シャ)

ASCII: +

phonetic value: unused

definition (single): joined situation (also mathematical plus ) (加わった、数学記号の+)

verb:

vi. (the subject) join (加わる)
vt. add, let (someone or something) join (加える)
{gd,25(joined)} : (the subject) also become (the situation of the following character or phrase) together :
shows the verb is not only about the subject, the subject joins to the situation of others.
(主語もいっしょに〜する)
: I too join to assist {25,46,63} it. (私もそれを手伝います)

When suggesting to do something with the other people or parson together, the idiomatic head with #01 and the verb work together.
(ほかの人にも誘いかける場合の言い回しには、次のように#25を組み込んだ接頭句を用いる):

: Let's walk{21,47,61} together!(いっしょに歩こう!)

main images in base overlays:

1) Related to join (参加・加わることに関係)
2) Related to addition (加えることに関係)
3) Related to the meaning of 'plus' (as the opposite of 'minus') (プラスのイメージで)
4) No relation to the meaning of 25; just related to the shape of its base/base overlay (文字の形に関係)

examples of base overlay:

Related to join (参加・加わることに関係)

{13(same),25}: approval, approve (v. with gd) (賛成)
{15(recognition),25}: knowledge, know (v. with gd) (知識、D動詞:知る)
{25, as 16(part)}: addition/supplement, add (vt. with ge) (追加)
{02(one),25}: integration (統合)
{25,68(heart)}: thoughtful (心をこめた)
{{15,68}consciousness,25}: careful (注意深い)
{{15,68,25},56action}: taking care
{{15,68,25},56action},65occupation}: career/baby-sitter
{10(place),25}: a place of meeting (待ち合わせ場所)
{{14(way),23(change),25}: turning on a/the switch (スウィッチを入れた状態)
:{36(time),37(nature),25,23(change)}: weathering, weather (vi. with #gd) (風化)
{{36,70}(term, length of time ,25}: time (length) needed for something (要時間)
{{46,63} hand,25}: aid, assist (with d-verb symbol ) (手伝い)
{55(want),25}: apply (志願)
: the head to say "let's do/be something/in some way together"
(いっしょに〜しようと呼びかける文頭)
{55,25,65(person)}: volunteer
{56(action),25}: participation, participate( with d-verb symbol ) (参加)
{56,25,65}: participant (s) (参加者)
{06(opposite),25}: defection, estrangement (離反)
{25,24(certainty)}: promise (約束)
{25,26(piled)}: gathering, gather (as d-verb) (集合)
{25,45(relation)}: combination, matching (組み合わせ)
{54(existence),25}: inauguration, installation (着任)
{66(plant),25}: plants which join others to survive: parasite (寄生植物)
{gc (preposition),25} : with (〜とともに)
`HF+ `{added power on the surface}}: pressure (for physics) (圧力)
`HF+p `sense of pressure (圧感)

Related to addition (加えることに関係)

{09(matter),25}: addition (追加)
{{51,58}(ability),25}: power up (能力増強)
{33,25(plus)}: sum total (合計)
{03line, 25(joined)}: drawing( the situation joining with line) (線描)
{14(way),25}: connection, be connected( as a d-verb ), connect( vt. as a e-verb ) (つなぎ)
{17(above),25}: addition on top of something (上乗せ)
{18(below),25}: addition on bottom (底いれ)
{19(in),25}: included, include (vt. with ge) (含んだ、E動詞:含める)
{20(out),25}: exclusion, exclude (vt. with eg) (除外)
{61(front),25}: addition in front (前付け)
{62(back),25}: addition in the back, add behind (e-verb) (後付け)
{47(accepted), 25}: income (収入)
{48(cover),25}: security (警備)
{{48,25}security, 24(related to law),46}: police (as an official organization)
{{48,25}security, 24(related to law),10place}: police station
{{48,25}security, 24(related to law),56occupation}: police officer
{21(heading),25}: increasing tendency (増加傾向)
{27(plural),25}: repeating additions (繰り返し加える)
{28(surface),25}: attached (付着)
{51(power),25}: power up, reinforcement (強化)
{52(heat),25}: heating, be heated (as d-verb), heat (vt. as e-verb) (加熱)
{25,38(human made)}: processed (加工)
{28(surface),{25,38}}: surface-processed (表面加工)
{05(non),25,38}: unprocessed (加工していない)
{10(place),25,38}: manufacturing or processing place (加工場)
{25,38,27again}: repairing/ repair (修理)

Related to the meaning of 'plus' (as the opposite of 'minus') (プラスのイメージで)

{25{39,68(feeling)}}: the feeling which works subjectively to the 'plus' direction: like, love, prefer (好き)
{25,{34,68}(value)}: good, goodness, become good (vi. with #gd), make something good (vt. with #ge) (いい)
{25,49(quality)}: good quality, become good (with #gd , make better (with #ge) (質的にいい)
{25,34}: benefit, advantage, profitable, gain, benefit( vi. with #gd) (得)
{{25,34},21(heading direction): advantageous (有利)
{{25,34},55(want)}: pursue profit (利潤追求)
{{25,34},24(certain): interest (on a loan/deposit kind of system) (利息)
{fortune + {25,34} profitable}: good-luck (幸運)
{37(nature),25} or {+09(intangible thing ) or {+50( tangible thing)}: mercy of nature (自然の恵み)
{46(function),25}: usefulness, effective (有効)
{67(life),25}: healing, cure (治癒)
{{67,25},65(occupation)}: medical doctor (医者)

No relation to the meaning of 25; just related to the shape of its base/base overlay (象形文字を構成)

{25,31(shape)}: cross as a shape (十字形)
{{33,34}ring + 25}: wheel (as the picture like symbol) (車輪)

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