square nail; square peg
Refers to a nail or peg with a square cross-section, used in traditional woodworking and construction. The 'square peg' gloss is a direct translation but less common in everyday English; the primary meaning is a square nail.
Square nails are sometimes used in the repair of old buildings.
Standard kanji spelling for 'square nail'.
Mixed kanji-kana spelling, sometimes used for clarity or in contexts where the second kanji is less common.
Compound of 角 (かく, 'square') and 釘 (くぎ, 'nail'). The reading is a straightforward combination of the on'yomi of 角 and the kun'yomi of 釘.