• firsthalf,
• firsthard,
• wisthand,
• firstand,
• dirsthand,
• cirsthand,
• virsthand,
• girsthand,
• tirsthand,
• fursthand,
• firtsthand,
• frsthand,
• fisthand,
• fristhand,
• firshtand,
• firsthhand,
• first hand,
• furst-hand,
• frst-hand,
• fist-hand

• first base,
• first-rater,
• first mate,
• first lady,
• fastened,
• first step,
• first cause,
• first-rate,
• first aid,
• first name,
• first water,
• firstborn,
• first state,
• firstly,
• first half.

The adjective form of the word "firsthand" is "firsthand".

The plural form of the word "firsthand" does not change. It remains the same as "firsthand" in both singular and plural usage.

The singular form of the word "firsthand" is "firsthand". It is an adjective that does not have a different singular form.