Is μαχομαι second aorist?

[Phoebus_Apollo]

I’m a little confused at the moment because some verbs like μαχομαι have aorist stems (different to the present stem) in brackets next to them when I look them up in my textbook (Reading Greek), but they follow 1st aorist endings…so for example, the aorist stem of μαχομαι is μαχεσα- and I thought if the stem is different in the aorist then it’s second aorist? But it actually follows first aorist endings (so ἐμαχεσαμην etc). I’ve come across this with other verbs to, like θεαομαι and γελαω
Would be grateful if someone could explain this for me?

[daivid]

@Phoebus Apollo

I’m a little confused at the moment because some verbs like μαχομαι have aorist stems (different to the present stem) in brackets next to them when I look them up in my textbook (Reading Greek), but they follow 1st aorist endings…so for example, the aorist stem of μαχομαι is μαχεσα- and I thought if the stem is different in the aorist then it’s second aorist? But it actually follows first aorist endings (so ἐμαχεσαμην etc). I’ve come across this with other verbs to, like θεαομαι and γελαω
Would be grateful if someone could explain this for me?

Because the 2nd Aorist is signalled by a change in the stem it does not follow that any change in the stem indicates a 2nd aorist. μαχομαι is simply an irregular 1st aroist (and the stem is μαχε- ).

[Hylander]

Without having seen your textbook, I suspect the aorist forms are provided in brackets not because they’re second aorists, but because they are in one way or another irregular or unpredictable from the present stem. μαχομαι is of course present, not aorist.