まっすぐ・真っ直ぐmassugu[3]nakadaka (mid-high)

1. na-adjective, adverb, nounstraight (ahead); direct; upright; erect
   あなたはきのう放課後ほうかごまっすぐ帰宅きたくしましたか。↗

   Did you go straight home after school yesterday?
2. na-adjective, nounstraightforward; honest; frank

• SynonymストレートNeutralA loanword for being blunt or for a straight pitch; also straight wins or drinks served neat, as in 「ストレートに言う」「ストレート勝ち」.
• Synonym直接的ちょくせつてきNeutralFor things happening with no one or nothing in between, as in 「直接的な原因」; the point is the absence of an intermediary.
• SynonymダイレクトNeutralA loanword meaning direct or nonstop, as in 「ダイレクトメール」; mostly used in compounds.
• Synonym一路いちろWrittenA written word meaning a single road; as an adverb, straight on and single-mindedly, as in 「一路邁進」. 「真っ直ぐ」 is the everyday choice.
• Synonym真直ぐますぐNeutralAn alternative way of writing 「まっすぐ」; when read 「ますぐ」 it is an older-sounding variant with the same meaning. In everyday writing, use 「真っ直ぐ」.
• Synonym直截ちょくせつWrittenWritten/formal prose for speech that is crisp and clear without beating around the bush, as in 「直截な表現」.
• Related率直そっちょくNeutralFor frankly saying what you really think, as in 「率直な意見」; centers on one's manner of speaking.
• Related正直しょうじきNeutralFor not lying and being honest, as in 「正直に話す」; centers on telling the truth, while 「真っ直ぐ」 centers on an upright character.
• Related単刀直入たんとうちょくにゅうWrittenA written idiom for getting straight to the point or starting a task directly (originally charging the enemy with one sword); 「真っ直ぐ」 also covers physical straightness.
• Related誠実せいじつWrittenA written/formal word for treating people sincerely and responsibly, as in 「誠実な対応」; centers on a serious, earnest attitude.
• Related実直じっちょくWrittenA written word for honest, steady and dutiful, as in 「実直な人柄」; 「真っ直ぐ」 stresses an upright character that takes no detours.
• RelatedすっとNeutralA mimetic word for a light, quick movement or something stretching straight up, as in 「すっと立つ」.
• Related素直すなおNeutralFor a mild, uncontrary character, as in 「素直に謝る」; centers on taking in what others say.
• RelatedありのままNeutralFor things just as they are, with no dressing up, as in 「ありのままの自分」; centers on being true to the facts.
• Related真正直ましょうじきNeutralFor being utterly honest and not at all slick; stronger in degree than 「正直」.
• Related真っ正直まっしょうじきNeutralFor being honest all the way through, holding nothing back; more emphatic than 「正直」 about being thorough.
• Related直線的ちょくせんてきWrittenA written word for moving one-way like a straight line; also figuratively for simple, one-track thinking, as in 「直線的な考え方」.
• Antonym曲がるまがるNeutralThe opposite of 「真っ直ぐ」: to bend or turn; also figuratively for a crooked mind.
• Antonym歪むゆがむNeutralThe opposite of 「真っ直ぐ」: to warp or lose its shape; also figuratively for a twisted character.
• Antonym斜めななめNeutralThe opposite of 「真っ直ぐ」: slanted or tilted; also a foul mood, as in 「ご機嫌斜め」.

For physical straightness or going directly, 「真っ直ぐ」 is the default. For frank speech pick 「率直」 or 「ストレート」; for not lying, 「正直」; for a mild, receptive character, 「素直」; for no intermediary, 「直接的」. 「誠実」「実直」「単刀直入」「直截」 are written-register options, 「真っ正直」「真正直」 intensify 「正直」, and bending is 「曲がる」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. まったくまがっていない様子ようす。
2. まっすぐに。