verb

• (transitive) To acquire possession of.
  "Looks like you’ve gained a new friend."
• (intransitive) To have or receive advantage or profit; to acquire gain; to grow rich; to advance in interest, health, or happiness; to make progress.
  "The sick man gains daily."
• (transitive, dated) To come off winner or victor in; to be successful in; to obtain by competition.
  "to gain a battle; to gain a case at law"
• (transitive) To increase.
  "Then they had bouts of wrestling and of cudgel play, so that every day they gained in skill and strength."

noun

• (electronics) The factor by which a signal is multiplied.
  "There follows the high and low-frequency replay equalization, which normally involves two adjustments with a further control allowing the replay gain to be set."

prep

• (obsolete) Against.

adj

• (obsolete or dialectal) Straight, direct; near; short.
  "the gainest way"
• (obsolete or dialectal) Suitable; convenient; ready.
• (dialectal) Easy; tolerable; handy, dexterous.
• (dialectal) Honest; respectable; moderate; cheap.